Made of brass, used for connecting two 1 inche NPT female threaded pipes, valves or faucets. Comes with a roll of ptfe tape, only apply it when having a leak issue, not necessarily used, just in case. Works steadily at temperatures from -65 ? to 250 ? (-53 ? to 121?), no problem in most environments. Suitable for air, fuel, gas, oil and water supply, the brass material guarantees rustiness and corrosion resistance for long lifespan. 2 hex nipple fittings included in package; Please notice the product is not allowed for potable water supply systems. Notice: Please be advised pipe size is not an actual measured size. It's nominal size instead. The Okelet brass pipe hex nipple fitting has 1 inche male threads on both ends. It can be used for many applications. The most common one is connecting two 1" female threaded pipes. A roll of PTFE tape will come with the hex nipple fittings. The tape is not necessarily used, only applying it when a leak issue occurs. The male National Pipe Taper (NPT) threads make the hex nipple fitting connect a female threaded pipe or other devices firmly. Made of brass, the fitting can work at temperatures from -65 ? to 250 ? (-53 ? to 121?), rustiness and corrosion resistance. It can be applied in both gas and liquid, like air, fuel, oil and water supply systems. Specification of each fitting: Weight: 2.7 Oz (76 grams) Length: 1.38" (35 mm) Size: 1" x 1" NPT Male to Male Included in package: 2 hex nipple fittings, 1 roll of ptfe tape