AS23053/7, formerly M23053/7, is a heat shrinkable polyethylene terephthalate, non-crosslinked insulation sleeving. This heat shrink tubing is available in Class 1 format for a single longitudinal seam that is thermally bonded or Class 2 format that is spirally wound that is resin bonded. AS23053/7 sleeving is used to provide a tight protective covering for relays, electronic coils and components, and small capacitor cans.