Both the locks that Skold has offered are 5 pin locks...please recheck your key profile. Here is a (bad...sorry!) pic of a 4 pin (top) and a 5 pin (bottom) key for a Master lock:
If you're not sure about the key and you don't have any tools/picks to count the pins, you can use the key itself...insert the key fully, then slowly pull out the key until you get a click and the key goes a little stiffer to pull. Count the clicks until the key comes out. Do it a few times just to be sure.
The 530 & 532 are steel bodied locks, whereas the 571 is aluminium...if you are not sure of the difference, put a little polishing compound on a rag and give the lock a few rubs. If the rag turns black, the lock will be aluminium.
From the last description you gave, did you mean that the edges are more square, or are angled? If you meant square, have a closer look at the 571 here:
http://www.masterlock.com/cgi-bin/prod_ ... =9&Go.y=10
If the polishing test doesn't show the lock to be aluminium, please disregard the link.
If possible, can you look at the way Master measures the locks, then re-measure yours in the same way?
The more
exact detail you can give, the easier it will be for us to help.
If it ain't broke.....pull it down and see how it works anyway!
