Postal certified, black leather. This shoe is built for those who spend most of the day on their feet or work in a job that requires a lot of walking. A special TP walking strike path outsole gives feet stability through each phase of the gait cycle. Inside is a Graphite Rollbar™. It's a piece of durable graphite that's biomechanically positioned in the midsole to maximize the stability of the back of the foot. Teamed with medial and lateral posts, it affords excellent motion control through each step. Single density polyurethane outsoles and midsoles give these shoes a lightweight cushioning ability that resists compression set.