To set your own combination: (REMEMBER: Combination can only be set when lock is open.)
 
1) INSERT ‘reset’ tool (A) (enclosed in package) in hole on side of lock.
2) PUSH key in and TURN key 90° in either direction (key automatically stays in this position). Failure to exert force while pushing key in will result in a failed attempt to set or reset combination.
 3) SET wheels (B) to desired combination.
4) TURN and remove reset tool. Lock is now set to new combination. BE SURE TO RECORD YOUR SECRET COMBINATION.
To Lock: SCRAMBLE the wheels and CLOSE the shackle.
To Reopen: DIAL your secret number and DEPRESS shackle.

To set your own combination:
 
Open and withdraw shackle. Note: For first time use, position wheels so that the numbers 0-0-0-0 aligns with the Master logo.
Pull spring-loaded metal end cap off.
Remove all four combination wheels.
IMPORTANT: Make sure the red clutchplate marks remain aligned with pointer.
Install wheels so desired combination aligns with pointer.
Snap metal end cap back into place (NOTE: If end cap will not mount properly, check wheels to make sure they are right side up).
To lock: Dial your new combination; close shackle, scramble wheels “to lock”. Be sure to record your secret combination.

To set your own combination:
 
With dials at 0-0-0-0, pull out the shackle.
Turn shackle 90° (1/4 turn) and press it down.
Continue pressing shackle and set the dials to your own combination.
Lift and turn shackle to the initial position.
To lock, turn dials to scramble combination.

To set your own combination:
 
With dials at 0-0-0-0, pull out shackle.
Turn shackle counterclockwise 90° and press it down.
Continue pressing shackle and turn another 90°.
Set the dials to your own combination.
Turn shackle clockwise back to the original 90° position.
Lift and return shackle to closed position.

To set your own combination:
 
With dials at 0-0-0, pull out shackle.
Turn shackle counterclockwise 90° and press it down.
Continue pressing shackle and turn another 90°.
Set the dials to your own combination.
Turn shackle clockwise back to the original 90° position.
Lift and return shackle to closed position.

To set your own combination:
 
OPEN lock and TURN shackle 90° to position I.
PUSH shackle in to lock until it “clicks.”
TURN shackle another 90° to position II.
SET dials at black indicator line to desired combination.
PULL shackle UP. VERIFY dials remained set to your combination before locking.
Lock is now set to new combination.
TO LOCK: Close the shackle and SCRAMBLE THE DIALS.
TO REOPEN: DIAL your combination and PULL shackle.

To set your own combination:
 
The combination is pre-set at the factory to 0-0-0.
While holding down the Cable Trigger Button, push down the Cable Head until you hear a ""click"".
Rotate dials to your desired combination.
Pull out Cable Head while holding down the Cable Trigger Button. Your personal combination is now set.
Note: Cable should be fully retracted for Step 1.

To set or reset the combination on your Master Lock 1550 backpack lock:
 
Align the dials to the previous combination. The factory-set combination is 0-0-0. 
Push in the button at the bottom of the lock. While holding in the button, turn the dials to your new combination. 
Once the dials are set to your new combination, release the button. The lock now has a new combination. 
Record your combination in a safe place.
For further guidance on how to set or reset the combination on your lock, please see the instruction sheet. (https://cdn.masterlock.com/masterlock/resources/documents/pdfs/1550dast_instructions.pdf)

To set your own combination:
 
With dials at 0-0-0 push in the shackle.
With shackle pushed in, set your new combination.
Release shackle and scramble wheels to lock.
Make sure to record your secret combination.

Unfortunately no. You cannot reset this lock without knowing the current combination. You'll likely need to purchase a new lock.

Unfortunately, you cannot reset this lock without knowing the current combination. You'll likely need to purchase a new lock.

A) My lock does not have a serial number:
To provide enhanced long–term security, Master Lock has discontinued imprinting a serial number on the lock body on combination locks sold through retail locations. For greater convenience, we encourage consumers to store their combination at our secure website, Masterlockvault.com, which is easy to use and offers 24/7 access. Unfortunately, we are unable to provide combinations for non–serialized locks. Please see examples of a serial number if you are unsure if your lock features one.
B) My lock has a serial number:
Please send your request to aftersalesmle@master-lock.fr and provide model and serial numbers.
Store your combination at Masterlockvault.com - a FREE service from Master Lock! The Master Lock Vault provides a safe & convenient place to store all of your confidential data for quick & easy access from your PC, iPhone, or any other mobile devices

It will take approximately 4 - 6 weeks for you to receive your combination once we receive the information.

To open a standard Master Lock combination lock (1500D):
 
Turn the dial 3 times to the right and stop on the first number of the sequence.
Turn the dial to the left, past the first number of the sequence, and stop on the second number.
Turn the dial to the right and stop on the third number of the sequence.
Pull up on the shackle.
Watch the instructional video.
 
How to open a Standard Combination Lock (1500D)

As a courtesy, Master Lock customer solutions group can issue you a replacement tool free of charge. You will need to supply the model number or an image of your lock. Please contact us to submit your request.

We will not provide lost combinations if the lock is attached to anything.

To locate the lock's Activation Code on the instruction sheet included in the lock packaging:
 
Remove the instruction sheet from the box packaging.
The Activation Code is located on the upper left side of the instructions.

For security purposes, the only way to open the lock is to use the combination. Resettable combination locks have a combination that is assigned by the owner of the lock. Therefore, Master Lock does not have record of the combination that the owner set.

Lubricate your locks with a lock lubricant.

99% of the time the lock is working perfectly, but consumers have forgotten their combination. If you believe your lock is defective please visit our Contact Us Page and fill out the contact form. A customer service representative will contact you within 48 hours.

For wheels that are hard to turn, we recommend using a WD40 for cleaning or washing the moisture out of a padlock but a good lubricant needs to be applied afterwards.

No. Master Lock does not reimburse for locksmith charges.

Your product is equipped with a disc cylinder which has the particularity to bring more security against picking. However, in order to insert your key into the cylinder, it is necessary that all the disks are perfectly aligned and that the key is fully inserted into the cylinder before turning it. We invite you to try this on your Master Lock product and contact us if the problem persists.

Generally, you should receive the replacement product in 2-4 weeks. This time may vary depending on the product.

You can review the use of your padlock that Master Lock recommends through the product page. Unfortunately, Master Lock will not replace the product due to an incorrect use.

Watch our lock maintenance video or view our Care & Service guide. If your lock still does not function properly, it may be defective. Refer to our Warranty Information to find out how to obtain a replacement lock.

All Master Lock padlocks are warranted to be free from mechanical defects for the life of the product. If a mechanical defect occurs, we will replace it free of charge. See Master Lock product warranty.