Kaba Mas X-07 Safe Lock: How to Open and Change Combination

Safe lock help · Kaba Mas

Safe lock troubleshooting › Kaba Mas › X-07 and CEX-07 (dial-powered, GSA)

The Kaba Mas X-07 (made by Mas-Hamilton) is a GSA-approved (Type 1F) high-security electronic lock. It has no battery: you power it by spinning the dial left, and a small display guides you. The CEX-07 is the same lock with a covert-entry feature. This guide covers how to power and open it, how to change the combination, and what the display symbols mean.

• How to open
• No battery
• Change the code
• Display messages
• Lockout
• Troubleshooting
• Manuals

Want the whole manual? Jump to the manufacturer download links.

Is this your lock?

• The Kaba Mas X-07, X-08, X-09 and X-10 are the locks used on government (GSA) security containers. The X-07 is the oldest of the four. Its manual carries the Mas-Hamilton name.
• A dial with a small LCD display and no keypad. You turn the dial to generate power and dial the combination as numbers appear on the display.
• The combination is three numbers. The lock works in single, dual or supervisory/subordinate mode.
• The CEX-07 shows CA (or CE) when you first dial: see the covert-entry note below.

How to power it and open it

Dial with complete full wrist turns. Stopping to re-grip leaves pauses that help the lock tell a person from a robot. The X-07 will not open, even with the right combination, if it thinks a robot is dialing. It can mistake a person for a robot if you dial more than 1.3 turns with no pause, dial with very short quick turns, or dial the whole combination in under 15 seconds.

1. Power the lock. Dial left (counter-clockwise) 4 to 6 turns. Numbers appear on the display.
2. Keep dialing left to the first number of your combination. Stop. The number shows on the screen.
3. Dial right (clockwise) to the second number. Stop.
4. Dial left to the third number. Stop.
5. Dial right. When OP (OPen right) appears, keep dialing right to retract the bolt.
6. Open the safe handle and the door.

Dual combination mode (two people)

1. The first operator powers the lock and dials the first combination (left, right, left), then dials right until E2 shows.
2. Within 40 seconds, the second operator dials the second combination (left, right, left). Either combination can go first.
3. Dial right. When OP appears, keep going right to retract the bolt.

Supervisory / subordinate mode

1. The supervisor powers the lock, dials the supervisory combination and then right until UL (Unlocked) shows. Now the subordinate combination alone opens the lock, as often as needed.
2. The subordinate powers the lock, dials the subordinate combination, then right to OP and on to retract the bolt.
3. To block the subordinate again, the supervisor dials the supervisory combination again and the display shows LU (Locked Up).

• The lock registers a number when you stop on it and then reverse direction.
• If the dial stays still for more than 40 seconds, the display goes blank and you must dial the whole combination again.
• If you pass your target number by 4 or more, keep dialing in the same direction until you reach it again. If you pass it by 3 or less, you can reverse direction slowly: the display jumps back 4 numbers, then dial slowly in the original direction to the number.
• Dial the whole combination again if a lightning bolt shows, or if the screen goes blank before the bolt is withdrawn.

No battery to change

There is no battery in an X-07. Spinning the dial left generates the power, and the lock is powered as soon as numbers appear on the display. If the display never lights up, dial left with steady, full turns (4 to 6 turns). If it still does not respond, call us.

How to change the combination

Before you set a new combination, you set the mode of operation. These steps set single combination mode. Dual and supervisory/subordinate mode set up the same way with a second combination: see the manual below. If you misdial or do not finish, the lock keeps the old combination.

1. Retract the bolt with the current combination, and release the bolt mechanism on the container so the dial turns freely.
2. Insert the Change Key into the slot on the back of the lock.
3. Dial left. The Change Key symbol appears. The lock never opens while that symbol shows.
4. Dial the current combination again.
5. Dial right until SL (Select Mode) appears. Dial left to 1 (single combination mode) and stop on it.
6. Dial right to set the mode. EC (Enter Combination) appears.
7. Dial your new combination: left to the first number, right to the second, left to the third. Then dial right until the display flashes the new combination.
8. The new combination flashes three times, then PO (Pull Out Change Key) appears. Remove the Change Key. The key symbol goes away and CC (Confirm Combination) appears.
9. Dial the new combination again to confirm it. When OP appears, dial right to retract the bolt. The new combination is set.
10. To cancel a combination you do not like, pull out the Change Key while it is flashing on the display, then reinsert it when EC returns.
11. Test the new combination several times before closing the door.

• If the door shuts and the lock closes with the Change Key still in the slot, let the lock power down (the display goes blank after 40 seconds; wait another minute), then dial right until it powers up and dial the current combination. If that does not work, call us.

What the display shows

The X-07 uses a display instead of beeps.

Wrong-combination count

The X-07 counts wrong combinations in a row and, once there are 3 or more, shows the count with a lightning bolt the next time you power it. The count goes back to zero when the right combination is dialed. The manual for the X-07 does not describe a timed lockout, so do not keep trying: if the right combination keeps failing, call us.

If it still won’t open

The display stays blank

Dial left with full, steady turns for 4 to 6 turns. The lock is powered once numbers appear.

I dialed the right combination and it will not open

The X-07 may think you are a robot. Dial the whole combination again with full wrist turns and a pause on each number, and take more than 15 seconds to do it.

The CEX-07 shows CE

A covert-entry condition has been set (for example the bolt was forced, or the bolt switch was tampered with). The normal combinations and the serial number will not work. Call us.

Download the full manufacturer instructions

More lock guides

• Kaba Mas X-08 (dial-powered, GSA)
• Kaba Mas X-09 (dial-powered)
• Kaba Mas X-10 (dial-powered, GSA)
• ← All safe locks

About this guide. This is an independent guide from Steve’s Lock, Safe and Alarm, a safe and lock dealer. Brand and model names belong to their owners and are used only to help you identify your lock. We are not affiliated with the manufacturers. These steps summarize the manufacturers’ own instructions; your lock may be a different version, so if anything here does not match what your lock does, follow your manual or call us. Always change codes with the safe door open, and test the new code several times before you close the door.

Steps last checked against the manufacturer documents on October 15, 2026.