Notes:Type 1: Outside Diameter:11mm, Inside Diameter:5mmType 2: Outside Diameter:12mm, Inside Diameter:8mmFeature:Brand: general purposeMaterial: stainless steelShape: cylindrical gearPosition: external gearTooth surface hardness: hardened surfaceShape: straight gearOutside Diameter:11mm/12mmInside Diameter:5mm/8mmWeight: 9g/11gPackage included:1x  Feeding Wheel