I used to scoff at people that used things like this because I used to feel that any type of container or bowl would work just fine to hold nuts and bolts while you worked on your project. Well, that all changed when I accidentally knocked over my container and spilled all my nuts and bolts all over the floor and some made it into the floor drain. My friend walked over with of these bowls and was holding it upside down as he gave me a hard time about my misfortune.
I now own one of these bowls and though I've had some mishaps, I haven't lost anything in awhile.
Magnet is not very strong at all. Not great will not hold a screw when tipped sideways. I reccomend buying a better product. It may be cheap, but it doesn't help. Now I bought something I am just going to replace with something better