I have a pair, they are fairly thin latex. I got them because they'd fit into my low volume SOF, but I wound up not liking them, hard to put on (put some cornstarch in them to ease putting them on) and the other reason I didn't like them for kayaking was they offer little protection for stepping on anything sharp, and they were too grippy... it was harder to enter the kayak because the feet wanted to stick to the floorboards and stuff... but maybe if the issue was having grip on a surfboard, where there was an aversion to wax, they may be good. They have little bumps on the bottom... so there would maybe be some elimination of water barrier between feet and board. But I have no experience how they'd grip to an epoxy-only or varnished board. One problem might be water getting into them, so you then are wearing water balloons on the feet... YMMV : )