This category includes heat shrink tubing and related products designed to insulate and protect wires and cables. It includes both heat shrinkable and non-heat shrinkable options such as spiral wrap, shrink tape, and non-shrink PVC tubing. Excludes lubricants, potting compounds, cover strips, rust inhibitors, air curtain doors, silicone conformal coatings, PVC and ABS cement pipe fittings, flanged bearing units, seals and O-rings, shaft collars, and other structural systems components.