44Pcs Nut and Bolt Thread Checker,27 Standard & 23 Metric,44 Male/Female Thread Gauges,Bolt Size Finder,for Quickly Identify and Verify

Good Quality and a very handy tool to have around. Saves a lot of time. Enabled me to bring some order to a very big mess of nuts, bolts and screws.

Other than being somewhat bulky, it is perhaps the best sizing tool for this purpose. Measures thread type without error. The thread sizing "cards" you can buy are popular but are limited in size selection and give ambiguous results. This tool nails it. The printing on each piece is slightly hard to read in poor light.Highly recommended, especially if you do re-fit and repair work.

Haven’t needed it since it arrived

First time I went to use it to check O2 sensor thread it wasn't there. Metric appears to be lacking 9 sizes. I understand the Odds maybe, but it shoulda had M18, M22 and 7/8.Standard sides does better, only 4 lacking, but I do use M18, 7/8 and M22 often enough that I will miss them. I'm betting there are also thread pitches this is lacking as well but don't know yet.Lacks-M9, M11, M13, M15, M17, M18, M19, M21, M22, M23Lacks-11/16,13/16, 7/8 and 15/16.Metric side black metal is very readable but the silver metal side w same font color is much harder to read.My O2 sensors are M18-1.5

Quick and to use. No more guessing or taking greasy bolts on a hardware store run.

I keep this in my truck box for when I need to measure something on the go. They are very accurate and nice to have when you need to know thread and bolt sizes.

I previously purchased a set of these thread checkers for my DYI shop. They were really handy, especially, for metric which I can not look at and recognize the size and pitch. However, the set I bought did not have sizes over 1/2’ diameter. After much frustration, I found these - small and larger diameter sizes. A great addition to a DYI shop. Metric bolts are a fact of life now and this set has the larger sizes. Spend the extra few dollars and don’t end up frustrated without, I paid $90 for a metric bolt eye hook vehicle tow hook that I could have easily (fabricated) welded (for about $5) but I had no way to determine the bolt size and thread pitch of the nearly 1” metric threaded hole recessed in the front car frame. This tool alone would have paid for itself with one use. But now I have it for lots of uses.

Overall it does the job but like so many thread checkers it’s not useful in some situations like when you have to determine a bolt and thread size in a hard to reach location. To address this I usually purchase bolts and nuts to complement the thread checker. I install the bolts and nuts on the thread checker giving me the flexibility I need in determining sizes and thread counts in virtually all situations. While screwing in one bolt I found it was only partly threaded. Fixed it by tapping it out but still you shouldn’t have to do this. Also, the black metric sizers scratch easily and none are particularly easy to read. It would be better if the sizes were etched into the metal.