They have a minimum 300 V rating and are available up to 60 A. All SC fuses are 13/32in Dia with varying lengths to provide a rejection feature that helps prevent over fusing (installing a 30 A fuse in a 20 A circuit). One half to 6 A SC fuses are fast-acting, while 7 to 60 A SC fuses are time-delay to permit temporary overloads to pass without nuisance openings.