For Sidewinder X1 extruder , with 66 teeth, which are treated without any burrs, which can the filament smoothly and quitely.This extruder is made of high quallity material, which is widely used in the industrial field, strong enough for feeding filament.For Sidewinder X1 Extruder Idler Arm. With smooth bearing, the feeding performanceItem Type: ExtruderSuitable for: 1.75mm FilamentCompatible with: For Sidewinder X1 Prusa i3 Ultimatecolour:Silver+blackMaterial:Plastic + Aluminumsize: diameter: 32mmPackage Contents:1 x Extruder ilder arm1 x Extruder Only the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.