Heavy duty steel construction with an electronic combination lock offering 1 million code variations. Fire-resistant for 30 minutes. Double-walled with composite insulation in the front door providing protection to locks and bolts. Electronic Combination Opening 4-10 Digit Code Length 25mm Width Locking Bolt Fire Rated to 30mins Anti-Tamper Freestanding Without Override Facility Electronic Combination Opening 4-10 Digit Code Length 25mm Width Locking Bolt Fire Rated to 30mins Anti-Tamper Freestanding Without Override Facility