I trimmed the rubber down so it only holds on to the bottom half of the cube.
Works well for my GF.
Me, I just put it in my pocket.
kamui makes one a bit pricey but the magnet is really strong almost cant knock the chalk off by accident I like it
| have had 3 magnet holders, they work alright but sooner or later you will forget to remove it and loose it in a chair or somewhere unknown.
Then I got a pencil type for your pocket, cheap but works super great and had it for a long time now. I cut the rubber holder down a bit and then use the chalk on my home table after it get worn down.
A friend just told me he puts a nickel under the chalk to lift it up a bit, then another as needed. I never tried that yet but I'm sure it will work great to get more life from your chalk.
Buy a cheap pencil type,