Up for sale is 1 Viton o-ring for a Pentair Rainbow series Chlorinatorlid, same as Manufacturers Model #R172009. This seal fits models: 300, 302, 320, and 322.Viton®/FKM has excellent resistance to chemicals, acidsand fuel as well as high temperature. It should not be used in applications of steam or hot water. The temperature range for this material is 5 to 400 F. Shippingcost is $1.58 forUSPS First Class that includes a tracking number. We never ship anything with just a stamp! Additional items ship at no extra charge, order as many as you want and the shipping stays the same. INSIDE DIAMETEROUTSIDE DIAMETERCROSS SECTION3-3/4"4-1/8"3/16"Our FKM O-rings meet or exceed the following ASTM D2000 Standard: M6HK710, A1-10, B38, EF31, EO88, F15, Z1:75Check our feedback and buy with confidence! We sell quality seals and gaskets and we back up everything we sell 100%.Payment for this item is by Paypal or Credit Card. Please contact us with any questions BEFORE buying. Viton is a registered trademark of DuPont Performance Elastomers. Powered by eCRATER .