The ultimate choice for cyclocross drivetrains Narrow/Wide tooth profile helps prevent dropped chains Ideal for 1x 9/10/11 system and single speeds Compatible with all 110/130mm 5 Bolt cranks Specially designed chamfers help resist mud build up 7075 Aluminum construction 130mm 5-bolt 42T 7075AL Black 1/9/10/11/12sp Narrow/Wide