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3/8" Dual Wall Heat Shrink Black

STH38B-4

$3.99

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This 3/8" diameter dual-wall heat shrink tubing features a 3:1 shrink ratio and adhesive lining for waterproof sealing, suitable for insulating 10-4 AWG wires. Made of polyolefin, it operates between -45°C and 125°C and activates at 100°C to provide durable, corrosion-resistant protection.

Diameter: 3/8" (before shrinking)
Wire Gauge Range: 10-4 AWG (approximate coverage after shrinking)
Shrink Ratio: 3:1 (shrinks to 1/3 original diameter)
Material: Dual-wall polyolefin with adhesive lining
Temperature Rating: -45°C to 125°C (-49°F to 257°F)
Activation Temperature: 100°C (212°F) - begins shrinking
Waterproof: Yes (when properly heated)

Marine Wire Splicing & Connections - Seal wire splices, terminal connections, and cable joints in boats where saltwater exposure requires waterproof protection that prevents corrosion and electrical failure.

Outdoor Electrical Installations - Protect wire connections in landscape lighting, outdoor outlets, and weatherproof junction boxes where rain, snow, and UV exposure demand durable, waterproof insulation.

Automotive & Trailer Wiring - Insulate battery cable connections, wire splices, and terminal ends in vehicles and trailers where road spray, moisture, and vibration require sealed protection against corrosion.

Underground Cable Protection - Seal direct burial splices, well pump connections, and irrigation system wiring where moisture, soil chemicals, and pressure require permanent waterproof barriers.

  • UL Listed
  • CSA Certified
  • Meets Mil-Spec 23053/4 standards
  • Free Shipping on orders $50+
  • Orders placed before 3pm PST ship same day
  • 30-day no-hassle return
  • Buyer may be liable for return shipping charges

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