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. The BirkoSport two-part system combines a BirkoCork?äó arch support, made from cork and EVA, and a shock-absorbing BirkoCell EVA foam top layer. Proper arch support helps distribute impact, absorbing shock and stabilizing the foot with every step. You can wear the layers together or separately to suit your comfort needs.