The MYFIT Derby Techsole is specially made for roller derby players but also park skaters. No reason these can't be used in any skate though as you can cut them down to size. The thin sole out of 3-D molded EVA material combines support and performance and doesn´t take too much space in your boots. Recommended for all skaters with bent flat feet to support the longitudinal arches to improve the position on your skates. MYFIT - upgrade your ride.