The SM 1253 is a premium, ultra-heavy-duty Starter Drive (Self Drive) Full Kit engineered specifically for Sino Truck (Howo/A7) heavy-duty commercial vehicles. Featuring a reinforced 10-tooth pinion, this kit is built to handle the massive cranking requirements of the WD615 and D12 series engines. Provided as a "Full Kit," it ensures a comprehensive replacement of the engagement mechanism for long-term reliability in logistics and mining environments.