This Advance E & I Systems heat shrink wire splice kit is designed for Repair and Installation of direct Burial underground wire a with 3 size 18-14 AWG leads. The Kit uses 16 -14 Butt connectors. The crimp on #18 AWG creates a good electrical conducting connection. The leads are individually spliced and an outer sleeve covers the whole splice for superior water proofing and strain relief. Advance E & I kits use only premium 3M dual wall shrink tubing and pure Electrolytic Copper connectors.