The GDB-63MA is a fast-acting glass tube fuse designed for circuit protection in low-voltage applications. It features a 5 mm × 20 mm physical size with nickel-plated brass endcaps and is rated for 63 mA at 250 V AC with an interrupting rating of 35 amps at rated voltage (50 Hz). The fuse exhibits a typical cold resistance of 12.5 O and a maximum voltage drop of 2000 mV at rated current, with a DC melting I²t value of 0.00057. Constructed to IEC 60127-2 standards and approved by UL (Guide JDYX2, File E19180) and VDE (File 40014109), this fuse is ideal for protecting sensitive electronic circuits, instrumentation, and consumer electronics where fast response and low breaking capacity are required.