The all new Pearl Izumi Race RD model provides benchmark performance and fit in a light and affordable package with top of the line features like our 1:1 Power Plate with built in Longitudinal Arch Support and Patent Pending 1:1 Anatomic Buckle Closure System. SELECT 1:1 Power Plate: SELECT Grade Nylon and Composite Fiber plate for lightweight stiffness and durability Direct Vent technology for cooling and drainage concave shaping for ultra low 7.0mm stack height, enhanced plate stiffness and anatomic support and built in Longitudinal Arch Support for optimal support, power, and efficiency. 1:1 Anatomic Buckle Closure: closure follows the natural anatomic shape of the foot to eliminate hot spots and remove pressure from your instep and an adjustable buckle mounting plate that delivers ultimate fit and flexibility patent pending. SELECT 1:1 Heel Cup: integrated Molded Power Band for benchmark heel hold and power transfer. SELECT Insole provides excellent Longitudinal and Transverse Arch Support.