Application:Fit for: Grip the filament of your 3D printer. Deep grooves give good hold for 1.75mm filament. Specification:Use For: MK7 / MK8 3D printerMaterial: Stainless SteelOuter Diameter: 12mm/0.47''Height: 12mm/0.47''Shaft/Bore: 5mm/0.2''Teeth: 40Thread Size: M3 Package Content:2 x Drive Gear