Drivegear Kits Bondtech drive gear kit in hardened and surface protected steel. Precision cnc-machined. Super sharp teeths for maximum grip on the filament. The perfect choice for a high-performance feeding system. Extremely high wear resistance for use with abrasive filaments. Product Details: Gear set for filament size 1.75 mm, primary gear with inner diameter 5 mm, secondary gear with two needle bearings,M3x2 setscrew and one 3 x 20 mm shaft. Gear set for filament size 1.75 mm, primary gear with inner diameter 8 mm, secondary gear with integrated needle bearings, M4x3 setscrew and one 4 x 22 mm shaft. Gear set for filament size 2.85 – 3.0 mm, primary gear with inner diameter 8 mm, secondary gear with integrated needle bearings, M4x3 setscrew and one 4 x 22 mm shaft. A Lithium based grease is recommended to use on the gear section and inside the needle bearings for low friction and to avoid wear. A small dab of grease is enough.