Garlock Gylon® 3505 sheet gasketing is made in a process that minimizes cold flow problems associated with skived PTFE gasket material. Made of virgin PTFE resin and glass microsphere fillers, for high compressibilty. Gylon® 3505 can be used in moderate concentrations of acids and some caustics, hydrocarbons, solvents, water,refrigerants, and cryogenics. Conforms to FDA regulations and is both NSF-61 and Oxygen Service certified. This material is unbranded.