WFLNHB Electronic Edge Finder Electronic Optical Edge Finder with Touch Point Sensor Beep Fit for CNC Lathe

I did not like that the ball diameter was 0.393", This is usually a standard size of 0.400". Also the shank should be 0.875" standard size, but is 0.893 diameter. Very hard to work with. Every thing else works very well. But I would not recommend buying this item, for experienced machinist. Or better yet, No one.

What this allows you do is just the mere touching of the ball connects the circuit so if you're using the centerline of the part is have to touch on all four sides without having to spin up the spindle and it's dead on as far as I can tell. Plus it's great for if you have blind touchoff spots. Do recommend!

Great accuracy, the probe works by grounding a circuit from your spindle through your part and to the rest of the machine. If you use a 123 block you can even use it as a Z probe, but never jog the probe down toward the table, you'll dent the probe and ruin it's accuracy. I prefer to probe in thousandths mode first, then switch to tenths and look for the first beep

I was not expecting the overall size of this when I bought. It's a pretty large probe and you likely don't have a toolholder for it, but it does work. The battery size also isn't standard and they aren't included, so be aware of that.

Poor machining the raw stock must have been undersized. My LED also did not lite. Poor quality control. Returning this one for a refund.

Would work if I needed an edge finder as big as my arm

The first thing the instructions tell you to do is check if the light works.Did that and NO LIGHT audio works but no visual.too much drama to send back SO NOT happy.