If you look carefully you can see one of the wholes is elongated, I don't remember which. It made no difference on mine, because the level was not installed correctly, so making the level, level made the pins out of plumb. It eventually broke. I really never used it anyways (part of my job requirement is to see things plumb and level so I'm used to it). It has nothing to do with pin gap.

Good site for the price. Been using mine for years and it has taken a beating. Had the CPU till last year. That was a huge rip off.20 bucks for a plastic lid. Think about that. The site was $85, CJ Pro 111, and the plastic cap was 20. I bought it without seeing it. Just a heads up to anyone thinking about it.