Like New Size 40 = 8.5 Womens USA I wear a 41.5 - 42 USA womens streetshoe and I think sizing down to 40.5 is a better fit for me. I would recommend for someone with a size 41 streetshoe or a someone who wears 41.5 but has a narrow foot or someone who wears a 41.5 and wants an ultra-performance fit. I took these to the gym 3 times and did 3 climbs in them each time. They are just a little too small for me. Amazing at overhang routes though and precise toe work. I replaced these with the same shoe in a size up and they work like a dream. More details: The La Sportiva Miura Climbing Shoes excel at hard rock climbing, power edging, and pockets. Full eight-panel Dentex-lined upper for unsurpassed fit and comfort Hook-and-loop closure for an absolute precision fit in an instant 4 mm Vibram XS Grip2 rubber for unparalleled grip Dynamic slingshot heel band focuses power to the toe box Permanent Power Platform (P3) keeps power down on slopers and in pockets Offset asymmetrical toe box places power and energy under the big toe, creating an inside-edge sweet spot Slip-lasted construction 1.1 mm Laspoflex midsole (forefoot only)