This micrometer is able to do measurement as large as 25 mm or 1” and it seems accurate to return to the exact 0.000 measurement when adjusted outward then returned to the fully closed position.The accompanying manual reminds me of microfiche, but photography allowed it to be expanded to readable size. I like the ease of the lever lock and find rotating the adjustment a smooth process. I did note some end play in the adjustment knobs, but pushing and pulling them has absolutely no effect on the measurement readings as it doesn’t move the spindle.Converting from millimeter to inch measurements is very easy and a necessary feature. This is my first micrometer and I’m pleased with its operation and accuracy though I usually use calipers for most of my fine measurement needs.

My initial reaction to this mike upon handing was not great. The plastic is not very high quality, and there's a lot of slop in the parts, which is particularly bad for a micrometer. But after playing with it for a while, I concluded that those elements are cosmetic, and that it does its job reasonably well. I took it apart to examine the functional components, and they seem to be of reasonable quality. (Photo attached.)Actual measurements seem repeatable and as accurate as one might expect for this type of micrometer: within about 0.002mm/0.0001". It's 0.5mm per rotation, which makes it pretty slow to get where you want; that's no different than most manual micrometers, but somehow it feels extra slow. There is absolutely no manual reading of the micrometer, not even anything to give visual confirmation. The thimble does not move back and forth with the spindle. The ratchet works on the large part of the thimble, not the speeder, which is unusual to me, but seems like it might be typical for this type of mike. The ratchet is just a thin leaf spring riding against unreinforced notches on the inside of the plastic thimble. I don't know how repeatable that will be long-term. (You can see the spring in the photo between the thimble and the frame.) There's a lot of in/out slop on the thimble, but that direction is not attached to the spindle. There's also a small amount of slop on the speeder, but, again, that's not attached to the spindle for that direction. They both make it seem sloppy, though. The way the rotation works is that the speeder is affixed to a tube with an internal groove. The tube surrounds the spindle, and the spindle has a pin that rides in the groove. As the tube is spun, it drives the pin, which rotates spindle along with the tube. The spindle is threaded into the barrel in the same manner as most micrometers. The spindle is thus screwed into and out of the barrel, but stays within the tube and doesn't move the thimble along with it. The spindle lock works well.You can zero the reading at any point. There's also an incremental mode. If you exit the incremental mode, you can't go back to the previous datum, you can only start a new incremental measurement. Switching between mm and inches is a long-press of the incremental button. It does retain both the zero and the incremental datum if you switch units, but it would be easy to mis-click and exit (or enter) incremental mode. Re-zeroing turns off the incremental mode. You can actually also hold down the on/off button and it will cycle through whether the zero button zeroes to 0, 25, 50, 75, 100, 125, 150, 175, or 200mm. I guess it's designed to work for different frame lengths. (Also, the 200 setting is broken. It can't display a "2" in the hundreds digit properly. I think the two left vertical members don't exist. Not that that makes any difference.) There doesn't seem to be any way to get the zero to be at inch multiples. It comes with two CR2032 batteries. There's no way that this has any sort of liquid resistance.I feel like this deserves 3.5 stars. The slop in the thimble really feels bad. But that's not really a functional problem, and everything else seems pretty good. The only thing that really bothers me on a functional level is that the ratchet will degrade and eventually destroy the thimble. But I'll round up.