The 2-520405-2 is Ultra-Fast FASTON series ultra-fast fully insulated FASTON Receptacle offers the advantage of a completely protected terminal and a wire crimp with comparable electromechanical performance to open barrel F crimp FASTON terminals. The user-friendly design combines easy mating with rounded corners. The ultra-fast FASTON receptacle housing completely encloses a tin plated copper alloy premier FASTON receptacle which has been stress-relieved for increased durability and resistance to abuse.