Nice Jazz.My Jazz bass has that same thing:
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Checking is one of those odd things to me. I have a white 1968 P bass with honest player wear thru the finish in a couple of spots, yellowing on all exposed surfaces, shrinkage of the pickguard and a fair amount of checking. But I also have a 1974 Mustang Guitar in Burst finish that has very little player wear, no obvious discoloration, no shrinkage on the guard, and no noticable checking. No checking on my 1977 Greco Thunderbird either. Why one has checking and the others don't seems odd to me. None have been refinished, FWIW the P bass is always stored in its case as was the TBird but the Mustang is always stored on a hanger.



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