I keep a set of these tools in my tool box and use them regularly when setting up lathes or mills. The four different sizes are very handy depending on what kind of interference I want to set up. As others have said, they're not entirely accurate, but very useful in situations where disabling them isn't a big deal.
Empire Level E250M: 12-Inch Heavy Duty Professional Combination Square with Etched π Stainless Steel Blade, Metric Graduations and True Blue Vial - Accurate Measurements Guaranteed
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π² Johnson RAS-1B Johnny Square: Professional Aluminum Rafter Square, 7'', Silver - Top Quality with 1 Square
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ICEPURE Plus 46-9690 NSF53 Certified Replacement For LG LT700P ADQ36006101, Kenmore Elite 9690 ADQ36006102, LFX28979ST, RWF1200A, LFX25978ST, LFXS30766S, LFXC24726S Refrigerator Water Filter,3PACK
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