3M MDT-A 12/3 Heat Shrink Tubing, Adhesive Lined, 4:1, Black, 1.2 m 7000037662

Medium-wall adhesive-lined heat shrink tubing with a 4:1 shrink ratio, providing a waterproof seal and excellent electrical insulation for cable joints and terminations. The cross-linked polyolefin jacket recovers from 12 mm supplied ID to 3 mm recovered ID, while the inner adhesive melts during shrinking to encapsulate and protect connections from moisture and corrosion.

Advantages

Adhesive lining creates a permanent environmental seal, preventing water ingress and corrosion. The 4:1 shrink ratio allows the tubing to slide over large connectors and shrink down tightly onto smaller cables. Flame-retardant polyolefin offers good UV resistance and operates from -40 °C to +120 °C, with a dielectric strength of 15 kV/mm for reliable insulation up to 1 kV.

Suitable for

• Insulating and sealing cable splices and joints
• Protecting automotive, marine, and outdoor electrical connections
• Strain relief and abrasion protection for wire harnesses
• Repairing damaged cable jackets in low-voltage systems

Key specifications

• Series: MDT-A
• Wall type: Medium wall, adhesive lined
• Material: Cross-linked polyolefin
• Shrink ratio: 4:1
• Supplied inner diameter: 12 mm
• Recovered inner diameter: 3 mm
• Length: 1.2 m
• Colour: Black
• Operating temperature: -40 °C to +120 °C
• Minimum shrink temperature: 120 °C
• Dielectric strength: 15 kV/mm
• Voltage rating: up to 1 kV
• Flame retardant: Yes
• UV resistance: Good
• Waterproof seal: Yes
• Standards: RoHS Compliant, UL Listed, CSA Certified

Recommendations

For best results, use a heat gun with a temperature of at least 120 °C and apply heat evenly from the centre outwards until the tubing fully recovers and adhesive flows from the ends. Ensure the surface is clean and dry before installation.