This device is made with an SB-50 and four pigtails of #12 wire with attached PP30 Connectors on the pigtails. This unit is not fused, external fusing recommended. You will need an SB-50 Gray connector to mate with this unit. This latter connector should then connect to a Battery or large Power Supply. The SB-50 is compliant with accepting up to #6 wire and thus can carry 50 AMPS of current continiously.