Features: The timing belts and pulleys are popular choices for Reprap, Prusa, MendelMax,3D Printer At least six teeth in contact with the pulley at a given time. This will reduce the possibility of sliding. GT2 pulley and belt are used together, and the profile with rounded teeth, which ensures that the belt tooth smoothly and accurately into the pulley groove Anti-backlash timing belt pulley with 20 teeth is one of the best choices for 3d printer construction. Introductions: GT2 belts and pulleys compliant (GT2 pulley) are popular choices for RepRap tests and traps. The series GT2 belts are specially designed for the linear movement. Use a profile with rounded teeth, which ensures that the belt tooth perfectly and accurately into the pulley groove, so that if one reverses the direction of the pulley, there is no place for the band to move in the groove. For the best performance, which is at least six teeth in contact with the pulley at a given time. This minimizes the possibility of sliding ring and helps to play in reducing even more. In practice, this means that you have made at least a pulley 12 teeth, and I usually try to get at least 16 teeth. GT2 belts: Material: Rubber Length: 5m Width: 6mm Pitch : 2mm Color: Black Step: GT2 GT2 pulley: Material: Aluminum Diameter: 16 mm Hole: 5mm Size: 16mm Teeth: 20 Color: silver Package Included: 1 x 5m GT2 Timing Belt 10 x 20Teeth Timing Pulley 1 x Hexagon Wrench