Camco's RV Blow Out Plug with Brass Quick Connect leaves your hands free to open faucets and flush out water lines without assistance. Screw the plug into your RV's city water inlet, open all drains and faucets, then connect your air compressor quick connect hose. It aids in the removal of water from your water lines. Aids in removal of water from water lines Quick connect attaches to air compressor quick connect hose Plug screws into RV's city water inlet Patented Completely clear your water lines