Rearfoot GEL Cushioning System: Attenuates shock during impact phase and allows for a smooth transition to midstance. Removable Sockliner: A sockliner which can be removed to accommodate a medical orthotic. Removable Sockliner: A sockliner which can be removed to accommodate a medical orthotic. Trail Specific Outsole: Reversed lugs provide uphill and downhill traction on all types of terrain. AHAR Outsole: Acronym for ASICS High Abrasion Rubber. Placed in critical areas of the outsole for exceptional durability.