I suppose I'll start off this review by listing what I like about it. It's a very handy tool. Goes much quicker than using digital calipers to find the diameter of the drill bits, and I was looking forward to using this instead of my calipers. The number markings are clear and easy to read- that is one reason why I went with this one over several other brands. The numbers are not only physically etched in the metal (so they won't rub off even after years of use) but also have black paint in the etchings for greater contrast and easier reading. After some use and handling, the black paint will come off (as it will for all etched and painted products like this), but it's a simple matter to reapply some paint to the etchings (nail polish is great, wipe it on, then wipe off the extra, and only place paint will be left is in the grooves/etchings). It's also a sturdy piece of metal (stainless steel too- so NO RUST!). It's well finished for what it is (don't expect a glossy chrome look). It's small enough that it is easy to store, but not small enough to easily get lost (I think the picture makes it look bigger than it really is). Actual dimensions are 2-3/8" x 6-3/4". So far, great product. After using it to sort roughly 100 or so drill bits, I had a small pile left over that didn't fit into any of the holes. At first I wasn't too worried about this, as fractional sized drill bits are only one of 4 popular ways to size drill bits (the other three being US Number 1-60, US Letter A-Z, and Metric), and these might have been one of those. So I pulled out my calipers to get the diameter of these left over bits. After measuring 4 or 5 that looked to be close to the same size, I realized that they were all within a thousandth of being a 25/64th (diameter of 0.390). So I then measured the 25/64th hole in this gauge and found that it was undersized by 3 thousandths (calipers read 0.387), which doesn't sound like a lot. That meant, however, that a properly sized 25/64th bit would not fit into the proper 25/64th hole on this gauge. I found the same issue with the 1/4, 5/64, 1/8 and 7/32 holes. Five holes in total were undersized. Some quick work with a mill brought all those undersized holes into spec and able to properly measure the size that was marked next to them. Not everyone has a mill (or even a drill press) and as such, may not be able to accurately fix this if needed. Keep that in mind. For fun (not really) I decided to measure all the other holes to see what they actually came in at. I found that the rest of the holes came in anywhere from 2-4 thousandths oversize from the decimal number listed by it. My guess is that the holes are supposed to be just slightly oversized so that the proper sized drill bit for each hole will slide into it with a comfortable, but snug fit (if they were machined to the exact size, it may be difficult to get a bit into the hole). So I'm not faulting this product for the holes that were just slightly oversized as that was probably intentional. 2-4 thousandths oversize is plenty accurate for measuring and sorting drill bits. So be aware that some of the holes may come undersized, and thus your drill bits will not fit. If you have calipers to check the holes of each size, and a drill press/mill to fix it, then it will take you only a few minutes to modify this gauge to work correctly if it does come to you with errors on some of the holes. If you don't have that, and you find yourself with left over drill bits after sorting, then you may want another one or a friend who can help you fix it. I'll be keeping mine now that it is fixed, and am very happy with how useful it is. Just be warned that it may not be entirely usable for you.
