Sta-Kon RCC6 YELLOW POLYCARBONATE BUTT SPLICE

The RCC6 is sized for 4 to 6 mm2 conductors. In AWG terms that range corresponds to roughly 12 and 10 gauge, so if you are splicing 10 AWG branch-circuit or motor leads this is the barrel to reach for. Conductors smaller than 4 mm2 will not be gripped properly by the crimp and should go into a smaller splice.

Yellow is the insulation color on the RCC6 and it is the standard trade code for the largest of the three common insulated terminal ranges, matching its 4 to 6 mm2 conductor capacity. Red covers the smallest wires and blue the middle range. On a panel build the color lets an inspector or the next electrician see at a glance that the right barrel size went on the right conductor.

Electrolytic copper is the barrel material on the RCC6. That matters for two reasons: copper keeps the resistance across the joint low so the splice does not run hotter than the conductor, and it is the right metal pairing for copper wire, which avoids the galvanic issues you get mixing dissimilar metals in a damp location.

A butt splice like the RCC6 joins two conductors end to end in one crimped barrel, so the finished joint stays slim and straight, which is what you want pulling through conduit, inside a fixture canopy, or in a tight junction box where a wire nut's bulk will not fit. The polycarbonate sleeve is a rigid insulator that resists cracking during crimping, unlike nylon or vinyl which can split. What it does not give you is a moisture seal, so for a wet or direct-burial location use an adhesive-lined heat shrink splice instead.

Yes, an insulated-terminal crimper is required. The RCC6 is a crimp-type splice with an insulating sleeve over a copper barrel, so it needs a tool with the correct nest for the yellow 4 to 6 mm2 range, crimped in the center of the barrel from each side. Pliers or a cutter's crimp notch will deform the sleeve and leave a joint that pulls out under vibration.

The RCC6 is a crimp butt splice with a copper barrel and it works best on stranded conductors, which compress evenly and lock into the barrel. Solid wire in the 4 to 6 mm2 range can be crimped but does not deform the same way and is more prone to backing out, so if the run is subject to vibration, stranded is the safer choice in this splice.

Order it as Sta-Kon RCC6. That is the manufacturer part number for the yellow polycarbonate insulated butt splice rated for 4 to 6 mm2 conductors. Country of origin on the part is Sweden.