It does the job pretty well. The rubber (silicone, I assume) grip holds onto the mini tins of Thinking Putty very well. It's a tight fit, but it needs to be. Getting the tins out is pretty quick and easy for adult hands but putting them back can take a minute because you have to stretch the holder back around the tin. Don't expect to be able to put them away in a hurry in other words.
The aluminum clip and the cheap rings holding the silicone to the strap just feel, well, cheap. I feel like the little carabiner is not likely to be able to stand up to any rough handling such as an accidental catch on a piece of furniture and i have already had the silicone holder come off of the ring once. I thought at first the rubber tore but instead it just slipped through the gap in the ring when it got stretched.
As inexpensive as they are i didn't expect pro quality but due to their construction i had to take off a star.
Still like them, I did end up buying three more after the first after all.