Mine slipped this year, but only when wet and some serious pushing on them.. I'm sure I could just tighten it a bit and it wouldn't budge. They slipped when climbing with this.. ~130lbs of meat alone. Probably the heaviest pack I've ever carried. I used a nice pair of Lekis this summer for a while, abused the hell out of them and they held up. Like the Black Diamonds el. carbon contours better though.
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But a better couple photos of the Black Diamonds..
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