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Best Choice HALLMERS 
HALLMERS Brass Straight 10mm Barb Hose to 1/2" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.Best Value Uenede 
Uenede Brass Hose Barb Fittings, 1/4" NPT Male to 1/4" Barbed Air Hose Fittings, Brass Air Line Repair Connectors for Co NPT thread size is a nominal pipe size and it does not represent the actual diameter. Please check the dimension drawingHALLMERS 
HALLMERS Brass Straight 12mm 1/2" Barb Hose to 1/2" NPT Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Red This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.uxcell 
uxcell Brass Barb Hose Fitting, 90 Degree Elbow 6mm Barbed to 1/8 PT Male Pipe Adapter Connectors 2pcs Product Name: Barb Hose Fitting; Size: 6mm Barb x 1/8 PT Maleuxcell uxcell Brass Barb Hose Fitting, 90 Degree Elbow 6mm Barbed to 1/8 PT Male Pipe Adapter Connectors 2pcs Product Name: Barb Hose Fitting; Size: 6mm Barb x 1/8 PT MaleHALLMERS 
HALLMERS Brass Straight 16mm 5/8" Barb Hose to 3/8" NPT Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Red This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.EMSea 
EMSea 2PCS 8mm to 1/2 Inch BSP Female Thread Barb Brass Fitting Connectors Hose Barbed Joint Adapter Coupler for Fuel Ai 1/2 Inch BSP internal thread to 8mm barbed hose tail fitting connector.HALLMERS HALLMERS Brass Straight 25mm Barb Hose to 1/2" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 1/2" BSP Male to 3/4" BSP Male Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Threaded Bushing Tubing Ada This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass Straight 8mm Barb Hose to 3/4" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer C This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.EMSea EMSea 2PCS 6mm to 1/2 Inch BSP Female Thread Barb Brass Fitting Connectors Hose Barbed Joint Adapter Coupler for Fuel Ai 1/2 Inch BSP internal thread to 6mm barbed hose tail fitting connector.HALLMERS HALLMERS Brass Straight 12mm Barb Hose to 1/2" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.X AUTOHAUX X AUTOHAUX 2 Pcs 19mm Outer Diameter Barbed to 3/4" BSP Hose Barb Tail Male Thread Adapter Brass Hose Socket Compression Application for motorcycle, car and truck.HALLMERS HALLMERS 1/8" BSP Male to 1/4" BSP Female Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Bushing Threaded Tubing A This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 3/8" BSPT Male to 1/8" NPT Female Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Threaded Bushing Tubing This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.ZoXureShop 21 PCS Premium Drip Irrigation Fittings Kit. Versatile 1/2" to 1/4" Connectors Ideal for Efficient Watering. Featuring B Comprehensive Watering System: Transform your gardening experience with a 21-piece irrigation kit featuring tees, elbowsHALLMERS HALLMERS 1/2" BSPT Male to 1/4" NPT Female Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Threaded Bushing Tubing This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.18% Off Kisangel Kisangel 100pcs Drip Irrigation Barbed Hose Connectors, 4/7mm PVC Drip Irrigation Connector for Tubing Garden Vegetable Versatile application: irrigation connectors ideal for vegetable gardens, flower beds, lawns, gardens, farms, home, greeQZWEXAZ 2Pcs White Thickened Pool PVC Fittings, 2" × 1-1/2" Male Thread Barbed Hose Fittings with Good Sealing, Versatile Pool P Size Design: The thread outer diameter is 2in, barb fitting outer diameter is 1-1/2in, fits corresponding inner-diameterHallmers HALLMERS 3/4" BSPT Male to 1/4" NPT Female Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Threaded Bushing Tubing This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 3/4" NPT Male to 1/4" NPT Female Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Threaded Bushing Tubing A This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 3/8" BSPT Male to 1/4" NPT Female Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Threaded Bushing Tubing This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 1/8" BSP Male to 3/8" BSP Male Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Threaded Bushing Tubing Ada This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 1" NPT Male to 3/4" NPT Female Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Threaded Bushing Tubing Ada This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 1/4" BSPT Male to 1/4" NPT Male Brass Pipe Fitting Coupler Thread Plumbing Hose, Hex Threaded Bushing Tubing Ad This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.EMSea EMSea 2PCS 10mm to 1/2 Inch BSP Female Thread Barb Brass Fitting Connectors Hose Barbed Joint Adapter Coupler for Fuel A 1/2 Inch BSP internal thread to 10mm barbed hose tail fitting connector.AcbbMNS AcbbMNS 5Pcs Brass Hose Barb Fittings, 1/2" BSP to 10mm Barb Hose Fitting Connector, Barbed Joint Adapter Air Hose Pipe 【Size】5-Pack 1/2 Inch BSP male thread to 10mm barb hose pipe fitting tail connectors.HALLMERS HALLMERS 3pcs Brass Barbed Fitting M6 Male Thread x 6mm Barb Hose Connector Metric Adapter Coupler M6 Male Metric Thread x 6mm BarbTopHomer 3 Pcs Solid Brass Pipe Fittings Barbed Thread Tail Connector Pipe BSP Male 12mm to 1/2" for Air Water Fuel Oil Gas HIGH QUALITY - Hose connectors are made of high quality brass, anti-rust and long lasting.HALLMERS HALLMERS 1/8" BSPT Male to 1/8" NPT Male Brass Pipe Fitting Coupler Thread Plumbing Hose, Hex Threaded Bushing Tubing Ad This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 1/4" BSP Male to M10 x 1.0mm Female Brass Pipe Reducer Fitting Connector Thread Plumbing Hose, Hex Head Threade 1pc Threaded Pipe AdapterHallmers HALLMERS Brass Straight 4mm Barb Hose to 1/8" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer C This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 3/4" BSPT Male to 3/8" NPT Female Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Threaded Bushing Tubing This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.Jotron Barbed Connectors for Drip Irrigation Systems, 4mm and 7mm Tube Fittings for Custom Garden Layout, 100-Pack Durable Plas Versatile Connector Set: Effortlessly connect and extend 4mm or 7mm tubing, specifically for 4mm and 7mm tubing, to creaEMSea EMSea 2 Pcs 1/4 BSP Female Thread to 10mm Hose Barbed Fitting Connectors Pipe Joint Adapter Couplers for Fuel Air Gas Wa 1/4 Inch BSP internal thread to 10mm barbed hose tail fitting connector.HALLMERS HALLMERS 3/8" BSP Male to 1/2" BSP Male Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Threaded Bushing Tubing Ada This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 1/2" BSP Male to 1/2" NPT Female Brass Pipe Fitting Connector Thread Plumbing Hose, Hex Head Threaded Tubing Ad 1pc Threaded Pipe AdapterHALLMERS HALLMERS Brass 3/4" BSP Male to 1/4" BSP Female Pipe Fitting Coupler with Hex Head, 15mm Length Threaded Tubing Adapter This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass Straight 19mm Barb Hose to 3/8" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 3/8" NPT Male to 3/8" NPT Female Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Bushing Threaded Tubing A This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS M8 x 1.0mm Male to M10 x 1.0mm Female Brass Pipe Reducer Fitting Connector Thread Plumbing Hose, Hex Head Threa 1pc Threaded Pipe AdapterHALLMERS HALLMERS 1/4" BSP Male to 1/4" NPT Female Brass Pipe Fitting Connector Thread Plumbing Hose, Hex Head Threaded Tubing Ad 1pc Threaded Pipe AdapterEMSea EMSea 2 Pcs 6mm to 1/4 Inch BSP Female Thread Barb Brass Fitting Connectors Hose Barbed Joint Adapter Coupler for Fuel A 1/4 Inch BSP internal thread to 6mm barbed hose tail fitting connector.12% Off EMSea EMSea 2 Pcs 1/4inch/6mm Brass Barbed Hose Fitting Coupler Connector with 1/4 Inch Male BSP Thread Pipe Nipple Fitting fo This fitting has a 1/4 Inch BSP male thread with a barbed hose tail.X AUTOHAUX X AUTOHAUX 2 Pcs 10mm Outer Diameter Barbed to 1/2" BSP Hose Barb Tail Male Thread Adapter Brass Hose Socket Compression Application for motorcycle, car and truck.GOLD DEER GOLD DEER 12Pcs Hose Barb Fitting 3/8" Barb to 1/4" NPT Male Thread Hose Barb Adapter Connector 1/4" NPT to 3/8" Barb Ho Packaging Includes:Insert 3/8xNPT1/4 inch outer wire pagoda insert *12, tape *1.Hallmers HALLMERS Brass 1/4" BSP Male to Female 75mm Threaded Straight Pipe Fitting Extension, Adapter Coupler Reducer Converter This is a handy brass pipe extension commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass 3/8" BSP Male to 1/4" BSP Female Pipe Fitting Coupler with Hex Head, 11mm Length Threaded Tubing Adapter This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 1/4" BSP Male to 3/8" BSP Female Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Bushing Threaded Tubing A This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS M16 x 1.5mm Male to 3/8" BSP Female Brass Pipe Reducer Fitting Connector Thread Plumbing Hose, Hex Head Threade 1pc Threaded Pipe AdapterHALLMERS HALLMERS M10 x 1.5mm Male to M10 x 1.0mm Female Brass Pipe Reducer Fitting Connector Thread Plumbing Hose, Hex Head Thre 1pc Threaded Pipe AdapterHALLMERS HALLMERS 3/8" BSP Male to M10 x 1.0mm Female Brass Pipe Reducer Fitting Connector Thread Plumbing Hose, Hex Head Threade 1pc Threaded Pipe AdapterHOINCO 21 PCS Drip Irrigation Fittings Kit for 1/2 inch to 1/4 inch Irrigation Tube Anti-Drop Premiun Quality Fitting,Barbed Lo 【1/2 in to 1/4 in Drip Irrigation】You will receive 2 tees, 1 on/off valve, 6 T-connectors, 3 6-way connectors, 2 elbows,HALLMERS HALLMERS 3/4" BSP Male to 1" BSP Female Brass Pipe Fitting Reducer Connector Thread Plumbing Hose, Hex Bushing Threaded This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS M18 x 1.5mm Male to 1/2" BSP Female Brass Pipe Reducer Fitting Connector Thread Plumbing Hose, Hex Head Threade 1pc Threaded Pipe AdapterOdorkle Odorkle Thru Hull Fitting, 1 Inch 316 Stainless Steel Straight Barbed Hose Connector with Half Threaded Interface, for B [Versatile Marine Applications] Ideal for a wide range of marine applications this straight thru drain fitting is perfecERGAOBOY ERGAOBOY Pack of 10 10mm Outer Diameter Barbed to 1/4" Female BSP Fittings Brass Hose Socket Compression Fittings Size: 10mm OD x 1/4" BSP SocketsHALLMERS HALLMERS Brass 3/8" BSP Male to 1/8" BSP Female Pipe Fitting Coupler with Hex Head, 12mm Length Threaded Tubing Adapter This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 1/4" NPT Male to 1/4" BSP Female Brass Pipe Fitting Connector Thread Plumbing Hose, Hex Head Threaded Tubing Ad 1pc Threaded Pipe AdapterHALLMERS HALLMERS 1/8" NPT Male to 1/8" BSP Female Brass Pipe Fitting Connector Thread Plumbing Hose, Hex Head Threaded Tubing Ad 1pc Threaded Pipe AdapterHALLMERS HALLMERS 1/4" NPT Male to 1/4" NPT Female Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Bushing Threaded Tubing A This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass 14mm Barb to 1/2" BSP Female Thread 90 Degree Elbow Fitting Connector, Threaded Hose Pipe Tubing Connecti This is a handy brass elbow fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass 1/4" BSP Male to Female 100mm Threaded Straight Pipe Fitting Extension, Adapter Coupler Reducer Converter This is a handy brass pipe extension commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 1/2" BSPT Male to 3/8" NPT Female Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Threaded Bushing Tubing This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 1/8" BSP Male to 1/4" NPT Female Brass Pipe Fitting Connector Thread Plumbing Hose, Hex Head Threaded Tubing Ad 1pc Threaded Pipe AdapterHALLMERS HALLMERS M12 x 1.5mm Male to 1/4" BSP Female Brass Pipe Reducer Fitting Connector Thread Plumbing Hose, Hex Head Threade 1pc Threaded Pipe AdapterHallmers HALLMERS M16 x 1.5mm Male to 1/4" BSP Female Brass Pipe Reducer Fitting Connector Thread Plumbing Hose, Hex Head Threade 1pc Threaded Pipe Adapterezqnirk 5PCS Metric Male Thread to Hose Barb OD Brass Barbed Pipe Fitting Coupler,M5x0.8 to 5mm X AUTOHAUX X AUTOHAUX 2 Pcs 12mm Outer Diameter Barbed to 1/2" BSP Hose Barb Tail Female Thread Adapter Brass Hose Socket Compressi Application for motorcycle, car and truck.HALLMERS HALLMERS 1/4" BSP Male to 3/8" NPT Female Brass Pipe Fitting Connector Thread Plumbing Hose, Hex Head Threaded Tubing Ad 1pc Threaded Pipe AdapterTopHomer Stainless Steel Barb Hose Fittings, 10mm to 15mm Female Thread Barbed Joint Adapter Pipe Connector Adapter for Fuel Gas Reliable Material: The hose tail end connector is made from 304 stainless steel with high hardness and corrosion resistaHallmers HALLMERS 1/4" BSP Male to M12 x 1.25mm Female Brass Pipe Reducer Fitting Connector Thread Plumbing Hose, Hex Head Thread 1pc Threaded Pipe AdapterHALLMERS HALLMERS 1/2" BSP Male to 1" BSP Female Brass Pipe Fitting Reducer Connector Thread Plumbing Hose, Hex Bushing Threaded This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass Straight 16mm Barb Hose to 3/4" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 1/4" BSP Male to 1/2" BSP Female Brass Pipe Fitting Reducer Thread Plumbing Hose, Hex Bushing Threaded Tubing A This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS 3/8" BSP Male to 3/8" NPT Female Brass Pipe Fitting Connector Thread Plumbing Hose, Hex Head Threaded Tubing Ad 1pc Threaded Pipe AdapterHALLMERS HALLMERS Brass 1/4" BSP Male to Female 150mm Threaded Straight Pipe Fitting Extension, Adapter Coupler Reducer Converter This is a handy brass pipe extension commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS M22 x 1.5mm Male to 1/2" BSP Female Brass Pipe Reducer Fitting Connector Thread Plumbing Hose, Hex Head Threade 1pc Threaded Pipe AdapterHALLMERS HALLMERS Brass 1/2" BSP Female to Male Thread 90 Degree Elbow Fitting Connector, Diameter Nominal DN15, External Threade This is a handy brass elbow fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass Straight 8mm Barb Hose to 1/8" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer C This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS M16 x 1.5mm Male to 1/2" BSP Female Brass Pipe Reducer Fitting Connector Thread Plumbing Hose, Hex Head Threade 1pc Threaded Pipe AdapterHallmers HALLMERS Brass Straight 16mm Barb Hose to 3/8" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.Hallmers HALLMERS Brass Straight 10mm Barb Hose to 3/8" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass 12mm Barb to 3/8" BSP Female Thread 90 Degree Elbow Fitting Connector, Threaded Hose Pipe Tubing Connecti This is a handy brass elbow fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.Hallmers HALLMERS Brass Straight 12mm Barb Hose to 1/8" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.Hallmers HALLMERS Brass Straight 14mm Barb Hose to 1/2" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.Hallmers HALLMERS Brass Straight 6mm Barb Hose to 1/2" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer C This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass Straight 14mm Barb Hose to 1/4" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass Straight 12mm Barb Hose to 3/8" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass Straight 14mm Barb Hose to 3/8" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS M12 x 1.25mm Male to 1/4" BSP Female Brass Pipe Reducer Fitting Connector Thread Plumbing Hose, Hex Head Thread 1pc Threaded Pipe AdapterHallmers HALLMERS Brass Straight 8mm 5/16" Barb Hose to 3/8" NPT Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Red This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.Hallmers HALLMERS Brass Straight 12mm 1/2" Barb Hose to 1/2" NPT Female Threaded Barbed Pipe Fitting Connector, Adapter Coupler R This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass Straight 19mm Barb Hose to 3/4" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.Hallmers HALLMERS Brass Straight 12mm Barb Hose to 3/4" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.Hallmers HALLMERS Brass Straight 19mm Barb Hose to 1/2" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass Straight 10mm Barb Hose to 3/4" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass Straight 6mm 1/4" Barb Hose to 1/2" NPT Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Redu This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.HALLMERS HALLMERS Brass Straight 16mm Barb Hose to 1/2" BSP Male Threaded Barbed Pipe Fitting Connector, Adapter Coupler Reducer This is a handy brass barbed fitting commonly used to connect lines for air, water, fuel, oil, and inert gases.