Product Description 3:1 Marine-Grade Adhesive Heat Shrink Tubing This premium dual-wall heat shrink tubing delivers superior protection and long-term durability in marine, RV, automotive, and off-grid electrical applications. The 3:1 shrink ratio ensures a tight, secure fit, while the adhesive inner lining creates a strong waterproof seal—perfect for connections exposed to vibration, moisture, and corrosive environments. Sold in 4-foot lengths. Each unit you order will include one continuous 4′ section. Need more? Add multiple to your cart—tubing is shipped in 4′ increments, not as a continuous roll. Features 3:1 Shrink Ratio: Easily conforms over irregular shapes and larger connectors. Adhesive-Lined Dual Wall: Inner glue melts and seals for exceptional moisture protection. Marine-Grade Durability: Thick-walled and flame-retardant, ideal for harsh environments. Color and Size Options: Available in red, black, or yellow and diameters of 1/4″, 3/8″, and 1/2″. High Heat Resistance: Rated for continuous operation at –45°C to 125°C. Specifications Shrink Ratio: 3:1 Operating Temperature: –45°C to 125°C Shrink Temperature: Begins at 70°C, fully shrinks by 125°C Material: Polyolefin outer with adhesive inner Voltage Rating: 600V Length: Sold in 4-foot sections Applications Marine and boat wiring splices and terminals RV electrical harnesses and repairs Off-grid solar, inverter, and battery terminal protection Automotive wire insulation and cable reinforcement Common Sizing Examples Many customers use the following tubing sizes for these types of wire projects: Unshrunk Diameter Approx. Shrunk ID Typical Wire Size / Use Case 1/4″ (0.250″) ~0.083″ AWG 14–16 wires, small terminals or solder joints 3/8″ (0.375″) ~0.125″ AWG 10–12 wire, small splices or ring terminals 1/2″ (0.500″) ~0.167″ AWG 6–8 cable, battery leads, heavy terminals Always measure your wire or connector outer diameter for best fit. Recommended Accessory For the best results, pair this product with a 120V Two-Setting Heat Gun by Ancor. It delivers consistent, even heat and makes shrink tube installation faster and more reliable—ideal for shop, garage, or dockside use. This marine-grade adhesive heat shrink tubing is your go-to solution for rugged, moisture-sealed electrical insulation. Its thick construction, excellent shrink recovery, and secure adhesive seal make it an essential for any marine or mobile electrical install.
