Shrink wrap and stretch wrap are often confused as they look very similar, but they perform very differently. When PE is used in a shrink wrap application, it is loosely placed over a single item or multiple items and will shrink around them when heat is applied, creating a tight, tamper-resistant seal of protection. When PE is used in stretch applications, it is formulated differently to be able to stretch around items.
The elastic memory of the wrap, along with its ability to cling to itself, keeps a tight layer of protection around the items. Stretch wrap is generally used for palletizing, AKA unitizing, multiple items on a pallet to keep them from shifting during shipment. Stretch wrap usually stretches about 100-300% where shrink wrap will typically only stretch to around 50-75% before breakage occurs.