LadyJane, I'm not familiar with this specific product, but what I know of magnetic clasps in general -- some are stronger than others, and sometimes they lose a little of the magnetic properties over time. The ones Bonnierose bought look good, but it's hard for me to judge from here (need to have them in my hands.) Basically -- the smaller the magnetic surface, the weaker the clasp is. So don't buy any tiny clasps unless it's for very lightweight jewelry.
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