Check the listing for details. Leather German Martingale Full Size Black Leather. Condition: Used. Listed at 35.00 USD. The Leather German Martingale is a high-quality training equipment used in equestrian sports. Made of black leather, this full-size martingale is designed to provide gentle control and leverage for lunging and training purposes. With its durable construction and precise design, this martingale is a reliable tool for riders looking to improve their horse's performance and obedience.