You know you have chosen the right electronic fuse when you choose a high speed semiconductor fuses from Mersen/Ferraz Shawmut. With fast acting fuse speed, 75A fuse amps, an interrupt rating of 200kA at 500VAC, 87kA at 500VDC, and a50qs series, this high speed semiconductor fuses is a must-have. As far as size goes, it is 1" in diameter. It is a nonindicating high speed semiconductor fuses. The voltage rating is 500vac/dc. The body is made of fiberglass material. It has a single element. Functionally equal to Bussmann FWH, Littelfuse L50S, you'll thoroughly enjoy its use. Standards include: CE, UL Recognized, Guide JFHR2, File 60314, CSA Certified LR12636. This high speed semiconductor fuses also meets the following environmental guidelines: RoHS Compliant.