Bolts optimized for single chainring Works with any bolt on a single chain ring without threading. Can also be used with other brands of single chainrings WALFT Tooth Chainring Bolts Set of 4 Short Limited Edition Espresso These chainring bolts are CNC machined from aluminum to create the perfect combination of low weight and great looking for bikes. These screws are specially designed for common 4-arm cranks. The bolt has a hole for 4mm hex wrench and the nut has a hole for 6mm hex wrenches, so there is no need for a wrench. Quantity: 4 pcs. Weight: 0.3 oz (8 g) (4 pcs). Material: 7075-T6 aluminum. Size: M8 x .75 x 5. Regulatory Torque: 7-8N