Ningjiang Zonghui Company manufactures various nonlinear helical tooth flank type of precision small-sized worm, worm shaft, gear and gear shaft by applying for international advanced milling method, which is a top method and makes machining most accurate and worm gear mating best. The general machining accuracy is up to Grade 6 of GB/10224 to 10227-88 (Chinese Standard), Grade 8 to 10 of AGMA (American Standard) and below Grade 9 of DIN 3974 (Germany Standard).

The products are served in widely fields which need worm transmission systems and worm screws, for examples, automobile component industry, such as worm shafts used in power windows & doors, seat adjusters, wipers, power rearview mirrors, and central locking systems medical appliances industry, such as hospital lift beds & chairs, and medical screws underground train, transmission system of power doors other industries like instrument & meter industry, spectacles industry, home appliance industry, mini special motor industry, power house door and window industry, and etc.