The Comet Aluminum is a high end performance blade used by some of the best skaters in the world. This blade gives you unparalleled feel and control in the corners| increasing your ability to transfer power into the ice as you accelerate through the corners. They are made with a 7000 series aircraft grade aluminum alloy making them not only strong but very durable. They have a 1.1mm thick bi-metal heat treated runner that reduces friction. BLADES ONLY| NO CLAP ARM.