1/4″ ID (before shrink) clear-blue adhesive-lined shrink tubing. 4 ft. piece. Made of polyolefin. Has 3 to 1 shrink ratio. The translucent color tint is matched to the terminal it can encapsulate: red for 22-18 gauge terminals and splices, blue 16-14 gauge terminals and splices and yellow 12-10 gauge terminals and splices. Wire gauges are imprinted on the exterior of the shrink tubing. The translucency allows you to see inside while installing or maintaining. Adhesive lining allows the shrink tubing to attach itself to the wire or terminal it is encapsulating giving it a watertight seal.