UL and CSA heavy duty S fuses are for use in air conditioners, furnace blower motors, swimming pool pumps, deep freezers or where motors frequently turn on and off. The S rejection base plug fuse is an industrial strength product and provides superior protection that will resist nuisance openings under repeated motor startups. Available in a wide amp range to permit exact sizing to motor load. Dual-Element, Time-Delay Plug Fuse125VAC, 15AMPRejection BaseCeramic Base with Rejection ThreadsCeramic Base with Rejection Threads