The Park Tool SW-40 uses the same world famous design and high quality materials as our three-sided spoke wrenches, with a unique four-sided wrench design for extra strength and support to help prevent slipping and deformation of nipples. Each SW-40 is made in the USA, and is precision-stamped, hardened and nickel plated for long service. Park Tool spoke wrenches are vinyl dipped to indicate the size at a glance.