Challenger ATR 7 GTX is built for running on both tarmac and terrain. It has been completely redone, compared to the 6th. It has received an increased sole thickness, 3 mm to be exact. Softer Eva. It is lighter than its predecessor, but despite this, the more aggressive studs in the outsole mean you get even better grip in the terrain. Here we have added Gore-Tex Invisible Fit Product Technology, to keep your feet dry in all conditions.