This 3" diamond wheel with a 1/2" arbor hole fit perfectly on my inexpensive Harbor Freight 5" bench grinder. The wheel is very heavy duty (weighed 12.6 oz), totally solid with a precision polished 1/2" hole for mounting. It ran so smoothly, I thought at first the wheel wasn't turning! I use it exclusively to sharpen my TIG welding tungsten rods while rotating the tungsten at the slowest speed of my battery drill. The result is almost a polished tip with straight longitudinal lines. Perfect! Takes about 10-12 seconds to sharpen each tip with just light pressure. Also, since it is a diamond wheel, there isn't any extra debris like you get from a glandular sanding disc. FYI, I turned the guard on the grinder straight up to see the smaller 3" wheel better. Works great!This thing tears thru tungsten without it leaving even a mark on the wheel. Looks like it will literally last my lifetimeI bought this 3 inch grinding wheel to sharpen my Tig welding tungston. Ordered it one day and got it the next. My Harbor Freight 3 inch grinder had to be ground just a slight bit inside for the wheel to fit but slid on using the original sleeve. Works perfectly. Very happy with Amazon Prime and this company supplying the wheel.Decent shipping, good value and so far I sharpened 20 carbide stump grinder teeth and it's going strong!Great value. I bought this to sharpen my tungsten electrodes. Works great and very fastFit my machine perfectly. Not overly expensive given I expect it to last a while..Its made to look like there's a lot of diamond substrate matrix attached to the wheel. But there's only a very very thin layer of diamond bonded poorly to a steel wheel.This seems to be a good diamond wheel, I'm using it to touch up carbide lathe bits. so far so good.