PETZL TRIGREST QUARK, NOMIC, ERGO is the perfect handrest that offer maximum comfort. . Adjustable hand rest for QUARK, NOMIC and ERGO: The TRIGREST hand rest is adjustable in height, without tools, on the shaft or the handle. It has two support positions: a brace for hand switching in the high position, and a brace for the index in the low position. The latter increases grip strength for leashless climbing and improves planting precision. The TRIGREST may also be used in a fixed position, without the index support.