Glass filled Nylon 66 5mm and 6mm adapters. Ultra high temperature. Ideal for connecting vacuum gauges for syncing the throttles valves. These adapters are easier to screw in and out than brass, especially when the engine is hot. Don’t transmit as much heat to the hoses or your fingers. Have a slot for removal by screwdriver. Will not damage the threads on the inlets. Includes nitrile sealing washers.