This is probably the last spoke wrench you will need. The 10 interchangeable tips are made of heat-treated steel for strength. The main shaft is CNC precision machined from 7075A aluminum and designed for optimum grip. Heads included are 5.0, 5.4, 5.6, 5.8, 6.0, 6.2, 6.4, 6.6, 6.8, and 7.0.