Once the security bags are sealed,any unauthorized attempts to break the seal will cause the universal STOP message to appear.Print along the sealed edges will also show any attempts.
Product features:

with tamper evident tape,hidden message is revealed when bag is opened,sequential numbering and barcode on individual bag,tearing off receipt with tracking numbers,custom color and logos,deep-freeze detection,heat indication available,waterproff,safe delivery,deter unauthorized read or theft.
Application:

security bags or envelopes are designed for a wide range of customers seeking tamper-proff security:

high secrity cash transit companies,police and judicial crininal divisions amassing trial evidence,security services transporting top-security documents,credit card companies.