Silicone Rubber Boot. White, 5/8″ Round Nut, For bat handle toggle switches, push button switches, and panel seal circuit breakers , Provides a watertight seal between switch actuator, bushing, and panel face , Mounting nuts are bonded to eliminate delamination , Thermal characteristics insure reliable performance over a wide temperature range , Inhibits the rotation of switches or circuit breakers subjected to low frequency vibration , Resists discoloring and cracking .