uxcell 17Pcs 17 Styles Gears Module 0.5 Robot Belt Pully Parts for DIY Toy Size: 17 Styles; Country of Manufacture: CHINA Material: Plastic; Net Weight: 8g Package Content: 13 x Plastic Gears 4 x Belt Pully; Main Color: White Gear Modulus: 0.5 Fit Belt Width: 2mm