A closed back design completely insulates power from the mounting surface. Each screw pair is one isolated circuit. Optional jumpers allow creation of common circuits.
| Brand | Blue Sea Systems |
| Amps | 20 , 20 , 20 , 20 |
| Fastener | #6 , #6 , #6 , #6 |
| Gang | 4 , 4 , 4 , 4 |