The SM 4622 is a heavy-duty Starter Drive (Self Drive) engineered specifically for the Tata T.C. (Turbo Charged) New Model vehicles. While it maintains the standard 10-tooth pinion common in the T.C. series, it features a specialized 10-spline internal bore to match the updated armature shafts of newer 24V starter motors. Utilizing a robust L-Type architecture, this unit is designed to provide reliable, high-torque cranking for Tata's modern turbocharged 6-cylinder diesel engines.