1. Material: aluminum alloy + ceramic bearing 2. Strong wear resistance, skeletonized for weight reduction 3. Sturdy and durable, not easy to deformation SDL-111. Inner diameter: 6 mm (fitted with reducer sleeve 5/4 mm) 2. Number of teeth: 11 teeth 3. Size: diameter 41 mm, thickness about 8.5 mm 4. Weight: 7.2g for single guide wheel, 12g for complete set SDL-131. Inner diameter: 6 mm (with reducer set 5/4 mm) 2. Number of teeth: 13 teeth 3. Size: diameter 51 mm, thickness about 8.5 mm 4. Weight: 10.2g for single guide wheel, 15g for complete set SDL-171. Inner diameter: 6 mm (with reducer bushing 5/4 mm) 2. Number of teeth: 17 teeth 3. Size: diameter 67 mm, thickness about 8.5 mm 4. Weight: single guide wheel 15.2 grams, the whole set of 20 grams
