3M 7000005943 3M™ Cold Shrink Insulator 8427-12 (OD 17.5-35.1 mm) 1kV, 10 EA/Case

The 8427-12 cold shrink tube goes on at 35.1 mm (1.382 in) inside diameter and recovers down to 16.8 mm (0.661 in). Anything under about 16.8 mm won't be gripped, and anything over 35.1 mm won't slide on. Measure over the finished splice or lug barrel, not the bare conductor, since the recovered tube has to seal on the cable jacket at both ends.

It covers 125 to 200 mm2, which is 246 to 394 kcmil, on single conductor non-shielded solid dielectric power cable. It's a one conductor cover, so on a multi-conductor run you apply one tube per phase.

The 8427-12 is 12 inches (304.8 mm) of relaxed tube and it accepts a connector up to 8.0 inches (203.2 mm) long. That leaves roughly two inches of seal onto the cable jacket at each end. If your lug or splice barrel runs longer than 8 inches, this size won't give you enough sealing length.

No. It's rated 1 kV and built for non-shielded, solid dielectric power cable in low voltage work. Shielded MV cable needs a shielded cold shrink splice or termination with a stress control layer, which this insulator does not have.

No flame and no tools. Cold shrink means the EPDM tube is pre-stretched on a removable core; you position it over the joint and pull the core ribbon out so the rubber collapses onto the cable. That matters in tight vaults, in pull boxes, and anywhere a torch permit or open flame is a problem, which is where heat shrink gets awkward.

It's insulation and sealing only, not a mechanical connection. You still make the joint with a compression connector, for example a Burndy YS6C Hylink long barrel copper compression splice, then slide the 8427-12 over the finished barrel to insulate and seal it. Keep the barrel you choose at or under 8.0 inches long so it fits inside the tube.

No - they do different jobs on the same joint. The Burndy YS6C Hylink is a long barrel copper compression splice, a metallic connector that mechanically joins the two conductors. The 3M 8427-12 is a cold shrink EPDM rubber tube that provides the primary insulation over that joint, rated 1 kV, with no tools needed to install. If you are splicing cable you typically need both: a connector to make the electrical joint and an insulator to re-jacket it.

Minus 40 to 90 degrees C, which is minus 40 to 194 degrees F. That covers outdoor pad and pedestal work in cold climates as well as conductor operating temperature on a loaded low voltage feeder.

It is RoHS 2011/65/EU compliant without exemption, and the EPDM rubber contains no chlorides or sulfur, which is why it's used against metallic lugs and armor without setting up corrosion. It is not halogen free, so if your specification calls for a halogen free cover, this isn't it.

The 8427-12 is sized for non-shielded solid dielectric power cable with conductors from 246 kcmil (125 mm2) to 394 kcmil (200 mm2), single conductor, at 1 kV low voltage. If your conductor falls below or above that window, or the cable is shielded, step to a different tube size in the 8427 cold shrink range rather than forcing this one - the recovered inner diameter of 0.661 in will not seal correctly on an undersized cable.

It ships 10 pieces per case, black EPDM, made in the United States. For a crew doing three phase work, one case covers roughly three full three-conductor splices with spares.