Details - 

The 430021 are C.K ratchet crimping pliers (0.5mm - 6mm), complete with full cycle ratchet mechanism. Designed for the safe and secure crimping of red, blue or yellow insulated terminals.

• Heavy duty body construction with hardened steel jaws
  
• Guaranteed for up to 30,000 cycles
  
• Factory set crimp pressures for the optimum connection safety
  
• Full cycle ratchet mechanism for safe, repeatable results and comfortable ergonomic handles