The Birkenstock Unisex Arizona FL WB Sandals have a classic style combined with the signature comfort of the Birkenstock footbed. The additional foam layer in the soft footbed provides extra comfort all day long. The deep heel cup supports the foot tissue and holds the heel bone firmly in its natural position. This provides the foot with nearly as much support when it is in a Sandal as when it is in a closed shoe. The heel mold activates the calf muscles, stabilizes the back of the foot and improves gait and coordination. The arch supports that run alongside the sides of the footbed surround the tarsal bones inside and out. This gives the foot the stability it needs when it takes a step. The support that runs through the middle of the footbed stabilizes the metatarsal bone. In this way, the transverse arch support helps ensure that the foot has a naturally straight and solid stance. There are raised indentations at the front of the footbed near the toes. Thanks to the toe grip the toes remain loose and spread out in their natural position. The indentations also support the natural rolling motion of the toes. The footbed is drawn up especially high at the front. As a result, the high footbed edge protects the toes during the rolling motion of the foot.