This works for my needs but to be honest I expected more accuracy. The mounting holes at the ends are offset by a few mm, I can't remember the exact dimensions from above, but e.g. B.: the left side holes are 10mm from the end, the right side is 12mm from the end. The difference is insignificant, but for someone it can be important. It also looks like the blocks that go with each rail should stick with that rail, so don't mix them all up like I did, I spent an hour trying to figure out which one goes with each rail. Again this has been mentioned in some other reviews but here I will say that you need M5 screws/bolts as the length only depends on the thickness of the material used. I used 5x25mm for the wood pieces on mine and 5x20mm for the rails and blocks.
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