Maple Speed Skating Clap system is taking over the world with its fast glide and its sturdy and reliable frame and pivot. Field serviceable springs, CNC machined 7000 series aircraft grade alloy tube and frame. 1.1mm thick proprietary Bi-metal runner with space age heat treatment. Tested to have the lowest friction of any blade in the world today. Also regarded as having the best edge holding of any blade in use today. Available to fit boots with 6.5"/165mm spaced mounts and can be ordered to fit boots with Long Track mount/spacing. 1,1 mm bi-metal blades 64 Hrc. The blades have received a special treatment in order to reduce the friction to a minimum. Precision ground blades Special designed steel tube for optimal flexibility; stable and yet easy to control For lighter skater Size : 15-34/35 - 15-6.5 - 15.5-36/37 - 15.5-6.5 - 16-38/39 - 16-6.5 - 16.5-40/41 - 16.5-6.5 - 17-42/43 - 17-6.5 - 17.5-44/45 - 17.5-6.5 - 18-46/47 - 18-6.5