A PET blister insert keeps a product in a defined position inside its packaging. It helps limit movement, separates individual components, and provides protection and support during handling, packing, retail display, and shipping.
PET stands for polyethylene terephthalate. During thermoforming, a plastic sheet is heated until it becomes pliable, formed over a mold, cooled, and trimmed into the required shape.
Unlike loose filler or a generic flat insert, a formed tray follows the dimensions of the product. Cavities, supporting ribs, finger notches, and raised sections can be added where needed. The result is a more organized interior that makes products easier to pack, inspect, remove, and present.
The insert may sit inside a rigid paper box, folding carton, clear plastic box, or another outer packaging structure. Its role is not to replace the outer box, but to work with it as a complete product packaging system.