This brass fitting provides a leak-free connection between my air-hose quick connect fitting and the water inlet of my RV.  Made of solid metal, this fitting is reasonably priced, provides adequate airflow to blow water from RV pipes and should last a lifetime.  For most motorhomes these are the steps to protect the plumbing from freezing:1.  Make sure that all water valves, the water pump, water heater and propane are turned off.  If the water heater has an electric element, turn off the breaker to prevent accidentally turning it on.  Empty the black water and gray water tanks, then fully open the drain valve on the fresh water tank and on the RV's water heater.2.  Set the output pressure of your air compressor to 50 psi or install aCamco 40055 Brass Water Pressure Regulatoror aValterra A01-1122VP Lead-Free High Flow Water Regulatorbetween the air hose and the RV's water inlet.  Then apply air pressure until all of the water is blown out of the water heater.  Leave the heater's drain valve open and close the heater's outer cover.3.  Shut off the air and operate the hot water heater's bypass valve(s), so that the water heater is bypassed.  Antifreeze should NEVER be put into the hot water heater.  If the check valve on the heater's hot water outlet is not working property it won't prevent antifreeze from being pumped into the hot water heater.4.  Re-apply air pressure to the RV's water inlet.  Starting with the highest faucet, which is usually the kitchen sink, open the hot water side and then the cold water side until all water has been blown out.  Repeat with the bathroom lavatory or lavatories, the shower, toilet and water pump.  This prevents water in the pipes from diluting the antifreeze.5.  Shut off the air and find the water pump.  There should be an inlet hose that can be extended to the bottom a gallon jug of pink (propylene glycol) antifreeze.  Turn the valve at the pump's inlet and remove inlet hose cap, so the pump can draw antifreeze from the jug through the inlet hose.  Then turn on the water pump.6.  Once again starting with the highest faucet turn on the hot water, then the cold water until the liquid runs visibly pink then shut off the flow.  Repeat at the bathroom lavatory, the shower and the toilet.7.  For most motorhomes with a single bathroom and shower, 1 2/3 gallons of antifreeze should be sufficient to protect all water supply lines and the pump.  The remaining antifreeze should be poured equally into in all of the sink traps, the shower trap and in the toilet to protect them from freezing.Some RV owners contend that just blowing out the water lines is enough to protect them from freezing.  That may be sufficient in mild climates.  However the leading RV manufacturers recommend that antifreeze be used to protect the water pump and those nooks and crannies where water may puddle in the plumbing even though it has been blown.  This entire winterizing process should not require more than about a half-hour.