4.90" Diameter

These magnets are very strong and very well made.They worked great for mounting a power strip on the side of my rolling too cabinet

WOW. These suckers are VERY STRONG. Just what I was looking for. I'm actually going to place them on the bottom of some emergency trailer lights that already have smaller magnets installed. The wind at 60 MPH won't blow these off!!!

Hold well. I use them to hang signs on the wall in my garage.

One of the most powerful magnets for lay use I’ve found! The hole allows for affixing bolts, bolt-eyes, etc. For my purposes that wouldn’t work, however a little Gorilla Glue and it’s held on to a solar motion light in all kinds of weather, without ever separating the magnetic hold!

But it appears that the shielding part is made of stainless steel which does not conduct a magnetic field very well. The only reason this matters is in the way I use these. I've tied them to winter golf tees, rubber tees with various heights. If the shiny side is up there is very little magnetic pull, needs to be flipped over to pick the tees up. I'm well into my 70's and need every convenience I can find! Other than that these are well made. I think I'll heat one up and see if I can break the glue bond holding the two pieces together.

Magnets work great, nice and strong. Worked to hang a fabric panel on a metal garage door. Make sure to use them in the correct way for a stronger magnetic pull.

Strong

I used two of these to attach a light bar to a JD 1025R ROPS. They're pretty good magnets and hold the bar in place decently well (when shaken REALLY hard, it fell off once). I'm quite happy with the magnets though.