One Large 4" Inch Diameter Hardened Chrome Solid Steel Bearing Balls, Vigorous Precision Balls

They are a good, solid steel bearing. Perfect for monkey fist paracord projects.

I use this for a good hand and wrist workout. Perhaps not its intended use, but that's alright by me.Good size to grip in the hand while remaining maneuverable. I made sure to clean off the packing grease before trying to grip it (don't want this to slip out and fall on my foot). So far it's still remained rust free, despite openly sitting on my desk between uses. Pretty shiny - enough to act like a distorted mirror - though I could give it a good polish if I want to take my handprints off it.Since I'm not sticking it in a machine, I can't speak to its concentricity or any other important factor. Feels pretty round, though.

Good tight tolerance, as expected. Working fine.

I bought for my artVery good quality and appearance

Very nice,Not as shiny as expected but it will buff!Oowa Chaka! Oowa chaka!

I am a hobby blacksmith and I purchased this ball bearing to create a tool for shaping and texturing copper ladles.I have made several copper as well as steel ladles on this bearing now. I’ve missed a couple times with my hammer but the bearing still has no mars or dents. Very tough smooth steel! It has also been out in my barn for months and there is absolutely no rust. This tool should last a LOOONG time.I was actually surprised at the affordability of this item, I had thought a bearing this big would cost a lot more. Very happy with my purchase.

resistance to rust -highquality -highsmoothness -highweight -lowgreat ammo for sling shot

I used these to remove dents from the intake runners on a GM TPI intake. Worked great they held up great with hammering through the tubes & without distorting.