Yes I have invested in a self inflating (hydrostatic [4" of submersion to inflate]) pfd and thankfully have not had to activate it (though I have been knocked down by and ice shelf and it did not inflate, but I'm pretty sure I wasn't 4" below). The non-hydrostatic ones, from my understanding can inflate when wet from the rain so I would be cautious with those... If you want the manual inflatable ones, MEC has the best price on those!! I'm curious to find out if mine will work and want to jump into a pool with it on, problem is, the cartridges are $70 to replace! Curiosity might get the best of me this summer and I might just have to forgo the $...
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