Designed biomechanically with the Vionic Technology, the VIONIC Mar Ankle Straps Sandals hug your arches and support your feet in comfort. The sandals are crafted with a premium quality leather upper, polyurethane lining, and built-in VIO MOTION Technology footbed featuring contoured arch support, with shock absorbing cushioning, deep heel cup to provide stability, and forefoot flexibility. The built-in orthotic is shown to be effective in helping to treat heel pain caused by plantar fasciitis or achilles tendonitis. Vionic Mar