The RV Supreme By-Pass Kit is the perfect choice to winterize your RV. It will also allow you to save money on the amount of anti-freeze required to fill your water heater each year. The RV Supreme By-Pass Kit is easy to install and will last the life of your RV. The plastic valves have free flow allowing you to by-pass your water heater all year with no disconnections. Protect the pipes in your RV this winter with the Supreme By-Pass Kit.