From the Manufacturer The Astro Pneumatic 9477 - 7 Piece Professional Quick Change Ratcheting Crimping Tool Set is a time saving tool that allows faster crimping of terminals and wire with a quick changing jaw design which requires no other tool to change the jaws. The unit features ergonomically designed steel frame handles with contoured rubber grips which make the tool easily operated with the left or right hand. Versatile kit includes 6 dies for many applications: A Jaw - Insulated Terminals: for AWG 22-18/16-14/12-10 or DIN 0.5-1.0/1.5-2.5/4-6mm², B Jaw - Non-Insulated Terminals: for AWG 20-18/16-14/12-10/8 DIN 1.5/2.5/6/10mm², C Jaw - Open Barrel Terminals: for AWG 20-18/16-14/12-10 DIN 0.5-1.0/1.5-2.5/4-6mm², D Jaw - Insulated Cord-End Terminals (small AWG.): for AWG 22/20/18/16/14/12 DIN 0.5/0.75/1.0/1.5/2.5/4.0mm², F Jaw - Insulated Cord-End Terminals (Huge AWG.): for AWG 10/8/6 DIN 6/10/16mm², H Jaw - Open Barrel Terminals & D-SUB, V3.5: for AWG 14/22/8 DIN 2.5-0.5/8-10mm²