No other slipper even approximates the performance of the Vim. Building upon a great last-from-the-past, the name of the game here is comfort that meets performance without sacrifice.  We decided to couple it with a stiff midsole and a beefed-up elastic closure system, creating a powerful tool that eats everything in its way, from overhanging rock to fiberglass slabs. The RS rubber outsole delivers the maximum amount of friction possible, ensuring that every edge or smear holds when the send is on the line.