Speed reducers are mechanical devices that help drive systems maintain optimal speed and torque for the application. Also known as gearboxes and gear drives, they lower the speed of rotation of the input shaft by a certain ratio and increase the power transmitted to the output shaft by the same ratio. Ratio multipliers increase the speed reduction and torque supplied by a speed reducer by a certain ratio and are suitable for parallel setups. Mounting bases, torque arms, and flange couplings are accessories used with speed reducers. They are often used in applications where the speed reducer will not be directly attached to the drive mechanism.