The Birkenstock BirkoSport Arch Support Insoles are a semi-rigid, two-piece, full-length insert that provides a deep heel cup for natural cushioning and shock absorption, a natural contoured arch support for longitudinal medial arch support, and a metatarsal support cushion with a gently raised platform for raising toes into the natural position. They are ideal for a low to neutral foot arch, BirkoSport are constructed of Birkenstock's patently unique blend of natural cork lined BirkoCork bottom piece insert with moleskin and a BirkoZell foam cushion top piece. When combined, these things provide superior cushioning and arch support for the entire foot length, however, both pieces can be worn separately. 100% Synthetic Two-part system includes arch support and shock-absorbing EVA foam top layer. Metatarsal pad provides extra cushioning under the ball of foot. Compressed foam heel cup absorbs shock, while helping stabilize the foot. BirkoCork (cork and EVA), BirkoCell EVA liner. Made in Germany. Size information How to measure your foot length Stand with the heel to a wall and put a measuring tape under your feet Read off the measured foot length in millimeters before your longest toe If you are between two sizes, choose the next higher, because feet are minimally greater under load You can also use our template: Download the foot measurement template SIZE TABLE WOMEN SIZES EU US UK mm 35 4-4.5 2,5 225 36 5-5.5 3,5 230 37 6-6.5 4,5 240 38 7-7.5 5 245 39 8-8.5 5,5 250 40 9-9.5 7 260 41 10-10.5 7,5 265 42 11-11.5 8 270 43 12-12.5 9 280 MEN SIZES EU US UK mm 39 6-6.5 5,5 250 40 7-7.5 7 260 41 8-8.5 7,5 265 42 9-9.5 8 270 43 10-10.5 9 280 44 11-11.5 9,5 285 45 12-12.5 10,5 290 46 13-13.5 11,5 300 47 14-14.5 12 305 48 15-15.5 13 310 49 16-16.5 14 320 50 17-17.5 14,5 325