Vinton is more of a trade name, but most o rings from viton are fkm/fpm, so compatible with hydrocarbons. I've rebuilt numerous cylinders over the years, and I generally go to a hydraulic place here to have them source all my seals(Mark hydraulics). Price difference is amazing. Last rebuild the vendor(Genie 34/19) list price for the kit was $275. Mark supplied each seal, total cost was $30.00. Generally if it says medical, Harley, or mercruiser, or now genie, it's gonna be expensive.