As its name suggests, the Osprey Variant 37’s greatest asset is its transmutability. In standard mode, this pack will bear a heavy guide load comfortably. Yet, when the approach necessities—the hip belt, frame sheet and lid—become superfluous, it takes only a minute to strip and cinch it down into a simple and light (34 ounces) alpine ascent bag. When I needed the hip belt out of the way of my harness but did not want to dismantle it, the Variant 37’s design allowed me to clip it around the front, through the tool holsters. Its versatility makes it a true ice, rock and ski mountaineering pack.