The Flexigrip 150M cable seal is certified by the Security Seal Testing Authority (SSTA) as an accepted HMRC customs seal, and for international shipping containers sent by sea freight, our Flexigrip 325M & Flexigrip 500M seals are ISO17712 'H' High Security Classification and C-TPAT compliant - accepted by customs agencies worldwide, including US customs. We offer the largest range of cable seals in the UK, with plastic and metal bodied seals, 1.5mm to 5mm cable diameters, custom cable lengths, bespoke security markings and up to 12 available colour shades.