The Timing Relay (OEM Part No. 3217929905) is an electrical spare part compatible with Epiroc underground mining equipment, including M4C, Simba H1354, SIMBA H1254 and Boomer-281 models. Manufactured with electronic components and plastic housing, it functions as a time delay control and circuit switching component in the electrical control system. The timing relay controls electrical timing sequences, improves automation accuracy, and supports reliable machine operation. Designed for harsh underground mining environments, this replacement electrical component delivers stable performance, excellent durability, and long service life for equipment maintenance and repair applications.