... protection 3. material:brass 4. minimum tolerance: +/-0.0001mm worm wheelOuter diameter: 300mminner diameter 240mm1. Anti-corrosion 2. Environmental protection ... 12 subsidiaries in china, dealing in chains, gears, sprockets, worm wheels since 1993;2. Delivery guaranteed: our production area of ... in producing all kinds of standard and non-standard worm wheel, so you can buy all the products you ...