Opti-Seal Crystal Clear Tubing Heat Shrinkable Butt Splices are our finest Butt Splice Connectors and are ideal for auto, industrial and marine use. Crystal Clear tubing sleeve allows crimped connection to be easily inspected. Color coded striping on barrel allows easy identification of the correct wire gauge size meant for use with the connector and also provide a visual guide to the correct crimping point on the connector barrel. Seamless barrel design ensures superior crimp performance and integrated wire-stop design on barrel prevents over-insertion of wire from either end. Internal adhesive in tubing seals and protects wires.