The Structure line has long been Nike’s stab at a stability / guidance trainer. The 26 marks a significant update: It uses a full-length ReactX foam midsole (no more Zoom Air in the forefoot) for cushioning and energy return. It includes a Midfoot Support System that provides structure around the arch and heel to limit excessive motion. The outsole has high-abrasion rubber in the heel and a lighter “blown rubber” in the forefoot for better transition (though durability in the forefoot is questioned). It has a stack height of ~ 38 mm in the heel, ~ 28 mm in the forefoot, giving a 10 mm drop. The upper is engineered mesh, with plush padding at the collar/tongue, integrated lacing bands for midfoot lockdown, and overlays in strategic zones. Weight-wise, in men’s U.S. size 10 it's about 11.3 oz (~320 g) and for women’s it’s ~9.2 oz. Nike also notes the shoe “fits small” and recommends going up half a size in many cases.