Red sealing Mastic strips 

Red sealing mastic strips are self-amalgamating, highly conformable sealing materials designed for moisture-proofing, environmental sealing, and electrical insulation support. They are widely used in cable accessories, telecommunications, and power distribution systems to ensure long-term protection against harsh environmental conditions.

Typically based on butyl rubber , these mastic strips remain permanently flexible and tacky, enabling excellent adhesion to a wide range of substrates such as polymer insulation, metals, and cable jackets.

Voltage Class: 1~35kV 

Dimension: Usually 300*30*2mm, 360*30*1.8mm and customized sizes.

Typical Applications

1. Cable Joints & Splices

• Filling gaps and irregular surfaces
• Providing moisture sealing around connectors
• Enhancing overall sealing performance in joint systems

2. Cable Terminations

• Sealing at lug/barrel interfaces
• Moisture blocking at stress control areas
• Supporting insulation systems in medium- and low-voltage applications

3. Heat Shrink & Cold Shrink Systems

• Used as an internal sealing layer
• Filling voids before applying heat shrink tubing
• Improving IP sealing performance

4. Cable Glands & Entry Sealing

• Secondary sealing for cable entries
• Preventing water and dust ingress
• Compensating for tolerance gaps

5. Telecommunications & Outdoor Connections

• Sealing RF connectors and coaxial cables
• Weatherproofing base station connections
• Protecting against humidity and corrosion

Material Characteristics

Compatible with heat shrink and cold shrink systems.