GM 56 Series were the standard OEM connectors used on 1950-1980 US made vehicles. Replacement Male Housing for .250\" Locking Male (PICO #1589). Unit then mates with Female housing unit (PICO #1863). Units were created to securely lock together with male & female contacts making a positive connection. Bodies can be disconnected for terminal replacement if needed. Male Terminal (PICO #1589) sold separately.