The HE721C2440 is a high-speed HyperFast® Fuse, manufactured by Littelfuse, that offers fast-acting protection from overcurrents. This fuse has a 24 VoltDC rating, a maximum breaking current of 4 amp, a melting I2t of 0.082A2sec, a voltage drop of 2.8V max, and a response time of less than 1 microsecond. It comes with a 6.3 x 32 mm ceramic body, a nickel-plated copper alloy cap, and a stainless steel insert. It is designed to be mounted on Faston terminals, disconnects, or lug-style terminal blocks, and is UL Recognized and CSA Certified. This HE721C2440 is ideal for protecting high-efficiency power electronic devices, such as inverters, solar panels, and home appliances, from dangerous overcurrents.