Birkenstock Sport Blue Footbed Arch Support Insoles Size: EU 38 (US: L7 M5) NEW in box! The Birkenstock Blue Footbed Sport Arch Support Insoles are a 3/4-length, rigid orthotic arch support insole that provides a deep heel cup for natural cushioning and shock absorption, natural contoured arch support for longitudinal medial arch support, and a metatarsal support with a gentle raised platform for raising toes into the natural position. Product Features: Rigid orthotic arch support insole 3/4-length footbed Orthotic arch design provides proper foot alignment and balances out foot impact areas for shock absorption, reduced foot fatigue, and potential of increased footwear life Ideal for neutral to high arched feet, and/or those seeking the Original Birkenstock sandal feel 73% cotton and 27% viscose synthetic fiber top cover BirkoCork: a cork and EVA foam construction provides flexibility and absorbs impact shock Moleskin anti-slip bottom coat increases durability and protects BirkoCork for longevity of footbed life Raised side flanges aid in controlling foot movement and stability Deep heel cup provides natural cushioning, shock absorption, and protects the heel bone for foot pain relief