Features: 1. Extended design with precision tooth profile for improved chain engagement; 2. CNC machined from a single piece for enhanced strength and durability, suitable for long-term cycling use; 3. Positive tooth design matches standard chain width; negative tooth design compatible with narrower chains; 4. Helps reduce vehicle weight by approximately 1kg; 5. Made from high-quality aluminum alloy material, durable and resistant to fading; lightweight construction ensures no added burden during riding. Notice: Please allow 13 cm deviation due to manual measurement. Actual color may vary slightly from the image due to differences in monitor settings and lighting conditions. Material: Aluminum Alloy Size: 32T: 136mm diameter 34T: 145mm diameter 36T: 153mm diameter 38T: 159mm diameter 40T: 169mm diameter 42T: 176mm diameter