, high quality. Durable and practical. Designed for linear motors. The GT2 pulley is used with the GT2 belt and is very convenient to use. The round tooth shape ensures installation of the belt teeth. Twenty teeth are in contact with the belt, minimizing the possibility of belt slipping. GT2 Belt: Material: rubber, aluminum, metal Color: Black Length: 2m Width: 6mm/0.23 inch Pitch: GT2 GT2 Pulley: Color: Silver Diameter: 16mm/0.62 inch Bore Diameter: 5mm/0.19 inch Height: 16mm/0.62 inch Groove Width: 7mm/0.28 inch Flange: Dual Teeth: 20 Setscrews: (two per GT2 pulley) Idler Pulley: Color: Silver Diameter: 18mm/0.71 inch Bore Diameter: 5mm/0.19 inch Groove Width: 7mm/0.28 inch Teeth: 20 : 1 Set (other accessories in the picture is not included) Package Contents: 1 X GT2 belt 2 X GT2 pulley 2 X idler 4 X twist spring 1 X hex wrench 4 X screws 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.