Mmf™ Tamper-evident bundle bags Tamper-Evident Bundle Bags, 15w x 20h, Clear, 4 Bundle Capacity Self-sealing adhesive closure has security features that exceed bank requirements for levels of tampering evidence. Security seal will display "VOID" message and rip if tampered with extreme cold source. Blue dots will appear on security seal when tampered with heat source. "Stars" on security seal will be distorted or disappear if exposed to salvia, solvents and chemicals. If seams are cut and resealed, microprint along sides will be missing or distorted.