Available in many types of gaskets, but the 3 most common types are described below: 1. Form-a-Gasket No. 1: Hard-setting sealant. A fast-drying, hard-setting, heavy bodied sealant ideal for repairing gaskets, etc. 2. Form-a-Gasket No. 2: Pliable-setting sealant. A non-hardening, heavy bodied pliable sealant for semi permanent assemblies. 3. Aviation Form-a-Gasket No. 3: A non-hardening, liquid, brushable sealant.