Everything you need to know about 12.7 mm gauges
You might not think about 12.7 mm gauges every day, but for anyone working with tight tolerances, they're basically the gold standard for quick, reliable measurements. Whether you're a hobbyist in a garage or a pro in a machine shop, that half-inch—or 12.7 mm—travel distance is a bit of a "sweet spot" in the world of metrology. It's enough range to handle most small parts, but compact enough that the tool doesn't get in your way. ...