It is made of rigid polypropylene with a very deep heel cup, very high medial and lateral wedge, can be used to help support a flatfoot and a rear foot deviation. The UCBL is a good choice for flexible flat foot in the pediatric patient. The UCBL is the traditional functional, rigid, and very controlling device intended to prevent subtalar pronation and midtarsal motion. It can be used to increase support and help prevent ankle sprains, absorb impact and relieve stress on the heel and ankle during activities. Best to use with:Lace-up or slip-on shoes Patient:Accommodative / Corrective, good for children with flexible flat foot, Maximum biomechanical correction.