Review on 📐 Precision Machinist Graduation Micrometer - Professional Grade by Kenny Marozas

For a 3-4 inch micrometer this is a very inexpensive instrument. It worked fine for my purposes (measuring the bore with a telescopic gauge) but I had trouble checking the calibration with the included 3 inch standard. I ended up using a 1-2-3 precision block to verify the factory calibration, which was accurate, and proceeded with my measurements. As far as I can tell the calibration issue was caused by the axes of the spindle and anvil. offset by about 1 mm. The photos show that one end of the calibration standard is perfectly aligned with the spindle, and the other end is offset relative to the anvil while the calibration is close to ideal.