The 011564723, type M 4/8.D2.SFD, is a double-deck fuse holder terminal block designed for DIN rail mounting. It features an integrated 24V LED to provide a visual indication of a blown fuse, simplifying maintenance and troubleshooting. The block utilizes a compression clamp connection, accommodates a wire size of 24-12 AWG (0.5-4 mm²), and is compatible with both 5x20mm and 5x25mm fuses. Its compact 8mm spacing and robust electrical characteristics make it ideal for circuit protection in industrial control panels and automation systems.