GYLON Full Face Gasket – 3530 Style, Black, PTFE with Graphite, Unbranded, 0.125 in Thick, 8 Bolt Holes, For 4 in, ASME B16.5 Class 150, AWWA C207 Class E, Class D, Class B Pipe Flanges

3530 FF GASKET 4.500″ID 9.000″OD Tighter Seal, Graphite-filled PTFE offers extremely low void content for minimal emissions Delivers effective, long lasting service against volatile hazardous pollutants (VHAP and VOC) Withstands high concentrations of hydrofluoric acids and other glass-dissolving media Will not support flame Will not support bacterial growth