RK1-720A pressure vacuum breaker kit is installed on the drinking water pipeline to prevent polluted water from back-siphonating into the drinking water supply 1.Includes :Plastic Washer, O-Ring, Spring, Poppet & Spider Assembly. 2.Size: 1/2" To 1" 3.Temp. Range: 33 Degrees to 110 Degrees F 4.Body Material Rubber, Plastic and Steel Easy to install Step 1:Close inlet and outlet shut-off valves before disassembling device. Step 2:Remove canopy screws and canopy. Step 3:Bleed off pressure by opening the No. 2 test Knob. Step 4:Unscrew the bonnet from the body Step 5:Remove the Plastic Washer, O-Ring, Spring, Poppet and Spider Assembly Step 6:After completing inspection, replace necessary parts and reassemble Product Including Spider Assembly Poppet Assembly Spring Plastic Washer and O-Ring Specifications for this item Part Number: RK1-720A Size: 1/2" To 1" Material: Rubber, Plastic And Steel Temp. Range: 33 Degrees To 110 Degrees F