Permatex Form-A-Gasket Sealants Options include No 1 Fast Drying/Hard Setting, No 2 Slow-Drying/Non-Hardening, and No 3 Aviation Sealant Liquid. No 1 cures to a hard, semi-flexible seal through solvent evaporation. No 2 is a slow-drying, non-hardening sealant. No 3 Aviation is a slow-drying liquid that changes to a pliable, tacky film through solvent evaporation. Pack of 12