Heavy-duty Fusetron type T time delay, dual element, Edison base plug fuse for critical circuit protection for swamp coolers, air conditioners, furnace blowers, swimming pool pumps, deep freezers or any circuit where motors turn On and Off frequently. Industrial strength, will not open under repeated motor startups. Brass threads (Edison base) thread into fuse receptacles. Extra large clear window makes it easy to see if fuse is blown. 125V AC, 10,000 A.I.C. UL listed.