The Schaller BM lightweight bass machine head weighs only 50% of conventional machine heads! The use of carbon and processed aluminium results in a lightweight tuner, without compromising on durability and precision. A special female screw guarantees precise positioning and fixing of the shaft. Hexagon banjo mounting screw and center pin. All parts are precision-crafted and surface-finished, the self-locking drive ensures an even, delicate and steady tuning. All string posts are made of high-grade brass and fitted into the housing with utmost precision, ensuring the best possible tuning accuracy and wear resistance. Gear ratio 1:22.