Tapered Caplugs can be used as either caps or plugs. Because they are tapered in design and made from highly pliable (or flexible) polyethylene, they can not only be applied to fit snugly but are readily removable...whether used for capping or plugging. Especially recommended for use on MIL Std. and SAE-type tube and hydraulic fittings and for threaded external and internal NPT fittings. Popular size Tapered Caplugs are stocked also in green FlexTemp, a flexible thermoplastic rubber for extreme temperature applications ranging from -90°F to 300°F (-68°C to 149°C).