The BK/GMC-4-R is a 4A medium time-delay glass tube fuse designed for overcurrent protection. It has a voltage rating of 125V AC and a high interrupting rating of 10,000A at that voltage. Key electrical characteristics include a typical DC cold resistance of 0.019 Ω, a maximum voltage drop of 120 mV, and a typical pre-arc I²t of 36 A²s. This 5 mm x 20 mm fuse is constructed with a glass tube and nickel-plated brass endcaps, designed to meet UL/CSA 248-14 standards. It is ideal for applications requiring low breaking capacity and medium time-delay protection.