Mammut "Grip ex" outsoles in The Gear Critic Posted August 31, 2016 · Edited August 31, 2016 by zub I guess Gripex is Mammut's new cheaper house-brand outsole. The boots (Ridge High GTX) are definitely not mountain boots, but were reminiscent in stature to a previous pair of Mammut mountain boots I owned in the past. They were on sale and fit beautifully so I bought a pair. On hike #2 for these boots, one of the major lugs near the toe box sheared clean off, and almost through the outsole. Upon closer inspection I found that the outsole had numerous places where rubber was shearing away in a weird shattered glass fashion. And one of the large under-toebox cleats was about to shear completely off as well. Dropped 'em back off at Second Ascent for warranty claim. Just an FYI.