VERY100 Plastic Shaft Rack Reduction Worm Gears Belt Pulley DIY For Robot 34 kinds Material:Plastic.Quantity:41pcs Our product includes gear, rack, pulleys, belts, and other transmission parts, and all the display pictures were taken in kind. 34 different kinds of parts and accessories in just one package, which makes it a perfect choice for laboratories, science education, DIY models, RC-airplane/helicopter repair, etc.