[Size]1/4 inch male air compressor quick plug to a female 3/4 inch garden hose inner thread and 1/4 Inch Male Quick Connecting Plug and 3/4 inch Male GHT Thread, this is standard size and can be applied in most cases. [Material]This RV winterize blowout adapter is made of heavy duty copper which is and it can withstand high temperature, sturdy and corrosion resistant. It is not easy to break or deform and can you for a longer time. [Application]Winterize blowout adapter is used to winterize garden hose, sprinkler systems, faucets, by blowing out water from the water lines or plumbing, prevent sprinkler system and pipe plumbing damage from freezing in winter. It can reduce the use of antifreeze, very Convenient, safe, healthy, environment friendly. [Easy to Use]Screw the water lines to the female or male threading side, then connect the quick plug to an air compressor line's female quick coupler. Turn on the air compressor, rotate around ball valve's stem to open/close and modulate the