The Viton CF gasket offered by MKS has a unique notching in the design, allowing less outgassing than most elastomer seals. Flange SizeGasket ODGasket IDMaximum Torque 1 1/3 inch 0.84 in. (21 mm) 0.64 in. (16 mm) 5 ft-lb 2 1/8 inch 1.29 in. (33 mm) 1.01 in. (26 mm) 16 ...