Ivyuma vy’umutekano vyitwa kandi ivyuma vy’uguhindura-evident stickers, bizwi cane nk’ivyuma vy’ibanga bifise igikoresho ca PET.
Ivyo PET negative bikora bidasanzwe kugira ngo bibe matrix (matrix akenshi ifise "VOID", "OPENED", yafunguye igice kidasanzwe canke umukiriya agaragaza. Iyo ikimenyetso gishizwe ku ruhande rw'ivyuma bifata amarira kuva pre-set matrix canke igishushanyo kiguma ku ruhande rw'ivyuma gishizweho kandi ntigishobora kuba undo,