This square is better made than the adjustable model I currently own. I haven't tested its accuracy, but the fit of the ruler in the hand (where the bubble level sits) seems snug and there is very little "play". I just got it so I haven't used it much, but I'm giving it 4 stars (instead of 5) because although the markings (gradations) are engraved, the contrast of the engraved lines with the ruler makes it a bit difficult to read. (I also want the ruler to be about an inch longer - which shifts the "0" point - I want to move my hand to coincide with that "0" point which would allow me to do a full 6 to measure inches. A precise detent that would allow the lever to be set to that exact position would be very helpful. It's just "out of the way" and I'm not criticizing this product for not having that feature.)
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