Safe Keeperbag Deposit Bags - 9" x 12" - 500 PackSAFE Keeperbags Face to face closure OPENED message appears when tampered with by freezing or chemicals Thermochromic ink changes colour when heated Random printed black diamonds prevent attempts to replace the seal Anti static foil liner releases without attaching to operator Dual sequential numbering and barcodes are large and easy to read Printing along the side welds prevents tampering by cutting