Worm Reduction Gear Set of Metal and Plastic DIY Production Motor Gear Description: Worm Reduction Gear Set of Metal and Plastic DIY Production Motor Gear Feature: 1 pcs of gear can match most gears, all combined into gears, this gear are suitable for shaft. Make of high quality plastic and metal material. For DIY science and small production, product design, mechanical model. Specification: Color: White. Material:plastic and mental. Size:as the picture show, the gear diameter is 28mm,the metal stick length is 27mm. Package included: 1X Gear and Metal Stick.