Double Output Shaft for a CALM series 63mm Aluminum Worm Gear Reducer. Image is for representational purposes only. Actual product may vary. Please refer to the specifications below for product details. WorldWide Electric offers cast iron, aluminum, and stainless steel worm gear reducers. Worm gear reducers are among the most compact and least expensive options among gear reducers, used to reduce input rotational speed and increase output torque.