Liquid tight Square lock flexible conduit is made by galvanized steel flexible inner core which is pressure coated with an oil resistant, high temperature grade of plasticized PVC. The PVC is keyed into the corrugations of the inner steel flexible core, which prevents the PVC from wrinkling when the conduit is bent to its minimum bend radius. The PVC coating provides a smooth outer surface onto which liquid tight compression fittings can be secured. Liquid tight steel conduit offers high mechanical strength combined with complete protection against liquids and dust. It is suitable for regular movements and vibration. All sizes made are of Inside Diameter & is Commercial Grade Quality.