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Contains two Viton-GF o-rings to fit the disconnect fitting we use in our fuel line disconnect kit. When the disconnect is parted, the o-ring is exposed and can get nicked by a sharp object.
Colder Products, the makers of the disconnect, supplies a repair nitrile o-ring, which this replaces. If you prefer that, you'll have to get one directly from them for 99 cents and pay them $10 shipping. Colder Products also supplies one Viton-A (they call it Viton, but we tested it and found it to be Viton-A) replacement o-ring for a couple bucks plus $10 shipping, which is inappropriate for gasoline due to extreme swelling. It is against our business model to sell you either one of those repair parts, given we have the part in a superior material (Viton-GF) at a lower price.