Replacement Key For Master Lock Coupler Lock

Question:

I have a Master #377 Universal Coupler Lock and I lost the key do you have a replacement key? Would your Master K1 key work? I do not have a key number.

asked by: NORRIS J

Expert Reply:

For Master Lock Universal Coupler locks 377DAT, 3774DAT, 378DAT and 379DAT, the replacement key is # MLK1. You will need to enter your key number to get the replacement that will fit your lock. The key number is not stamped on the lock, so if you do not know the number on your lost key, you will need to replace the lock. To remove the lock if it is on your coupler, you will need to drill out the lock core.

If you purchase another lock, I recommend writing down the key number in a location you will remember.

expert reply by: Jason S