A GT5 pulley is a specific type of toothed (timing) pulley designed to work with GT5 timing belts, featuring a circular tooth profile for precise, high-torque power transmission, common in automation, CNC machines, and robotics for accurate positioning with minimal backlash. Made from materials like aluminum, they come in various bore sizes (for motor shafts) and tooth counts, ensuring reliable engagement with GT5 belts for efficient mechanical power transfer in demanding applications.