The biggest technological upgrade in the jumping stilt industry - in 8 years! Why are the CZs so much better than any other jumping stilt? For years 99% of all jumping stilts were made by (2) authorized global manufacturers. Most parts on ALL jumping stilts were virtually the same. (Look - they are!) Until now!!! The Air-Trekker CZs now trump all existing jumping stilts models in quality and performance. Nothing is even close. Literally one of the coolest pieces of sporting equipment available to mankind! The lightest most advanced jumping stilts on the planet ..CZ-A ADULT (also see the new Air-Trekker CZ-A EXTREME Model listed separately). Jump up to 3-5 meters high. Run over 20 miles per hour. The newest technology at the best prices on the globe. New Spring Manufacturing Technology Hi-Tech nanometer: delivers small volume light weight ultra-responsive with good elasticity. Durable foam knee bar with NEW protective straps. Brand is distributed exclusively under royalty terms of German aerospace engineer Alexander Boeck. These are spring loaded top quality jumping stilts available directly from the importer/licensee at the lowest prices on the planet. VIP: As a beginner you should buy IN your weight category. Just stay in your weight category .and your CZs will come alive. They bend super easy yet shoot you up with power and speed. For Example: If your weight is 142 pounds you should buy the CZ60s. If your weight is 185 pounds you should buy the CZ80s. You should be at least 140 pounds to enjoy the Adult Model CZs. The CZ frame is completely redesigned: New materials and shape: High strength aluminum lithium. (Same material used to create the space shuttle gas tank.) While the M115 is simply extruded/bent aluminum. The CZ does not have an aluminum sleeve on the lower leg for weight reduction. The CZ\"s support brace under the footplate was redesigned as 145 degree tubular arc which reduces the concussion of external force on the spring. It s also much li