These small, nickel plated Park Tool Metric Wrenches can be used on brakes, derailleurs, etc. CBW wrenches are nominally 1/8" (3.2mm) thick. Park Tool Metric Wrench Features Compact open ended wrenches in the most popular bike sizes High strength steel with a nickel plate finish Perfect for use on brakes and gears Made in the USA and covered by Park Tool's legendary limited lifetime warranty More info