I inherited a bike with a rear suspension that needed some work, but the pivot point was just behind the center line of the crank consisted of two metal hinges, two bushings and a screw to hold everything together. One of the swivel mounts required a 12mm hex and the screw was about 6mm. Most metric hex sets go up to 8mm and the set of 12 might as well be 8 but no! The repair was already completed, but this part of it caused the odd error in the process.