Heat shrink tube HellermannTyton 323-20400, black, 1 m length, dia 4–12 mm, pack of 15

HellermannTyton 323-20400 heat shrink tube is a black polyolefin sleeve supplied in 1 m lengths and packaged as 15 pieces. Designed to shrink over a range of conductor and cable diameters, this tubing provides electrical insulation, mechanical protection and environmental sealing for cable joints, harnesses and connector terminations. The tube covers nominal diameters from 4 mm down to a reduced diameter and up to 12 mm before shrinking, allowing flexible use across a range of wiring and repair tasks.

Advantages

The heat shrink tube offers reliable insulation and strain relief for splices and connectors while maintaining a compact profile after shrinking. Its polyolefin construction provides good electrical resistance and mechanical durability against abrasion and handling. Supplied in pre-cut 1 m lengths and packed in multiple pieces, it facilitates efficient inventory use and reduces waste when working on multiple cables or assemblies.

Suitable for

• Electrical insulation of splices and connector joints
• Strain relief for cable transitions and terminations
• Protection against moisture, dust and mechanical wear in wiring harnesses
• Repair and maintenance tasks for automotive, industrial and consumer electronics

Key specifications

• Color: black
• Material: polyolefin (heat-shrinkable)
• Length per piece: 1 m
• Pack quantity: 15 pieces
• Nominal diameter range (before shrinking): covers approximately 4 mm to 12 mm
• Shrink ratio: typical for general-purpose polyolefin tubing (enables secure fit over smaller diameters)

How to use

Slide the appropriate length of tubing over the cable, splice or connector before making the electrical connection when possible. After positioning the tubing over the joint, apply uniform heat with a heat gun or other controlled heat source until the tubing shrinks tightly around the component and conforms to the underlying shape. Allow the tubing to cool and inspect the seal to ensure full contact and coverage of the exposed area.

Usage recommendations

Select a tubing diameter that, before shrinking, easily fits over connectors and assemblies but will contract adequately to form a tight insulation layer. Use a regulated heat gun at an appropriate distance to avoid overheating surrounding components; maintain even motion to achieve uniform shrinkage. For applications requiring enhanced environmental sealing or mechanical protection, consider using adhesive-lined heat shrink variants or additional protective sleeving as needed.