Steel Safe Engineering offer a strong room vault door. The outer layer of the door slab is of tough tested quality plate of 12 mm for Class-C and 30 mm thickness for Class-B door It is further reinforced by a composite thick layer of double duty barrier This dual protection is provided over the entire lock case. The total thickness of protective layer is 90 mm for Class C and 105 mm for Class B. A standard feature on all models of door, this sensitive device is triggered-of when an attack is attempted on the lock through the keyhole with any instrument. This automatic re-locking device guards all the key locks.