Single-wall heat shrink tubing is reliable and strong plastic layer that can be applied to cabling and components to insulate wires and protect them against abrasion and strain. Think of it as “indoor” heat shrink. It is best used for electrical wires or cabling that is unlikely to be exposed to outside elements like water, moisture, chemicals, etc.

Dual wall heat shrink tubing is lined with an adhesive glue to ensure the inside of the tube seals tightly around the wiring. This provides a secure cover to prevent moisture from entering the tube as well as doubling the strength of the protective layer. As heat is applied to dual wall heat shrink tubing, the adhesive flows along the tubing as it is melted. This provides an extra tight fit and defensive shield.