Tamper-evident seal. The original color of the sticker is white or silver grey. After the surface of the object is torn off, the VOID/OPEN text will appear on both the sticker and the object. Even thou the glue on the object can be removed, the sticker will still have the text VOID/OPEN and can no longer be used. This material can be applied to surfaces that are bent and is generally used for product warranty or sealing purposes.
Once tampered with, the text "VOID" or "OPEN" is revealed.
Tamper-proof label, seal tapes, food seals, tow truck tamper evident seal etc