The Aven Tools 10188 Crimping Tool for Insulated Terminals (22-18, 16-14, 12-10 AWG) features a built-in ratchet that applies the pressure necessary to ensure a complete crimp every time. The crimper is equipped with a safety release function that allows you to stop a faulty crimp before the crimping cycle is complete. The precisely milled, hardened steel dies have individual crimping slots for each wire size from 22-18/16-14/12-10AWG; sizes are color coded on the die for easy identification. The dies can easily be changed by sliding them out of the frame - no tools are required. The durable rubberized grips make the crimping tool comfortable and easy to use.