Rearfoot GEL Cushioning System: Attenuates shock during impact phase and allows for a smooth transition to midstance. AHAR Outsole: Acronym for ASICS High Abrasion Rubber. Placed in critical areas of the outsole for exceptional durability. Solyte Midsole Material: A lighter weight midsole compound than ASICS' standard EVA and SpEVA. Also features enhanced cushioning and durability.