Raychem HTAT Heat Shrink

Raychem HTAT is a 4:1 dual-wall adhesive-lined heat shrink tubing from TE Connectivity. Available in five diameters (8 mm to 32 mm as supplied), it is the most widely used adhesive heat shrink in motorsport wiring harness production.

HTAT vs ATUM

HTAT and ATUM are both dual-wall adhesive-lined heat shrink tubings from TE Connectivity / Raychem. HTAT is the preferred choice for motorsport applications:

	HTAT	ATUM
Shrink ratio	4:1	3:1 or 4:1
Operating temperature	−55°C to +125°C	−55°C to +110°C
Material	Irradiated modified polyolefin	Irradiated modified polyolefin
Adhesive inner liner	Yes	Yes

The higher temperature rating (+125°C vs +110°C) makes HTAT better suited for harness sections routed near engine and exhaust components. The 4:1 ratio provides greater size range coverage from a single tube.

Motorsport Connector Boot Sealing

HTAT is the economical alternative to dedicated moulded heat shrink boots. A short length is slid over the connector backshell before assembly, then recovered in place after the connector is built — sealing the cable entry and providing strain relief. This method is standard practice among professional motorsport wiring loom builders and is used extensively in Clubsport-class builds and by European harness manufacturers.

The built-in thermoplastic adhesive liner provides the environmental seal on recovery — no additional epoxy is required for standard motorsport use.

Fitting Tip

If the selected HTAT size is slightly too small to slide over the connector backshell, use expansion pliers to open the tube end gently before fitting. A small amount of force is sufficient — do not over-expand. This is a standard technique used by professional harness builders.

If the recovered wire exit end is too large to seal tightly around the wiring branch, gently push and hold the end in place so the hot adhesive bonds to the wire. Be careful — the tube has just been heated with a heat gun and will still be very hot.

Available Sizes

SKU	As supplied	After recovery
HTAT-8/2-0-SP	8 mm	2 mm
HTAT-12/3-0-SP	12 mm	3 mm
HTAT-16/4-0-SP	16 mm	4 mm
HTAT-24/6-0-SP	24 mm	6 mm
HTAT-32/8-0-SP	32 mm	8 mm