Primefit's compressed Air to Water blow out fitting provides a quick and easy way to clear out the water lines on your RV or Sprinkler system. The Quick Connect has standard 3/4” water hose threads and connects directly to your RV's water inlet port. Left over water in the plumbing after winterization can dilute antifreeze and place your pipes at risk of freezing and potentially bursting. To use, drain your water lines and leave all faucets on/open. Thread the Primefit Air to Water blow out fitting directly to your RV's water inlet. Using an oil-free air compressor, set the compressor's outlet pressure to a MAX of 50 PSI. Then attach the quick disconnect coupler (at the end of your compressor's hose) directly to the Air to Water fitting - just as you would attach an air tool or accessory. Keep connected until lines are empty.