Available in 8, 6, 4, 2, 1/0, 2/0, 4/0 AWG with stud options (1/4", 5/16", 3/8", 1/2") — select above. Included Components 10pcs 4 gauge-3/8" wire connectors, 10pcs of 3:1 heat shrink tubing. The marine grade 3:1 heat shrink tubing is UL & CSA certified (rated 600V / 257°F), thick and durable than other 2:1 shrink tube.