The very best transmission decision is when large transmission reduction is required. A worm equipment is related to a helical equipment with a throat cut to boost the outer diameter of the wheel. The throat enables the worm equipment to wrap fully close to the threads of the worm. By cutting the threads on the worm instead than the tooth, and by changing the quantity of threads, different ratios can be achieved with no altering the mounting arrangement. A unique attribute of worm gears and worm equipment assemblies is their capability to avert reverse rotation.