The STIHL 42077002500 Drum Coupling with Pulley is a genuine OEM replacement part designed for STIHL TS 400 Cut-Off Saws. This essential component ensures proper clutch engagement and power transfer, maintaining the saw's cutting efficiency and reliability. Manufactured to STIHL's rigorous standards, it provides a precise fit and durable performance. With approximate dimensions of 76.2 mm length, 76.2 mm width, and 38.1 mm height, and a weight of 0.113 kg, this drum coupling is crucial for the smooth operation of your equipment.