Eaton Bussmann Fuse: 20 A, 600V AC, 2-1/4 in L x 13/16 in dia Fuse Size, Cylindrical Body, 450V DC

Fast-acting, nonindicating UL Class J fuses open within seconds of being exposed to overloads and short circuits. Also called fast-blow Class J fuses, they are highly sensitive to changes in current flow and don't tolerate temporary overload currents or power surges. They have no indicator for identifying a blown fuse, so they're sometimes used with an indicating fuse block or cover.

UL Class J fuses have a high interrupting rating for protecting against short circuits and are ideal for IEC motor starter applications. These 600VAC fuses are not interchangeable with any other UL fuse class. They are current-limiting to prevent electrical damage by disconnecting circuits before they're exposed to the full magnitude and duration of an overcurrent.