3M™ Scotchlok™ Copper Long-Barrel Connector 11019, up to 35 kV, 750 kcmil, Black, 3/Case. 3M™ Scotchlok™ Copper Compression Connectors, 10000 Series are one-piece, standard-barrel, seamless copper connectors and are designed to cover a wide range of conductor sizes from 6 AWG through 1000 kcmil (MCM).