JUMPSOLES PLYOMETRIC TRAINING PLATFORMS - MENS MEDIUM 8-10 1/2 100% authentic and in very good condition with the original box! Jumpsoles are the world's most popular tool for increasing your vertical jump! Plyometric platforms that attach to your shoes! Jumpsoles focus your body weight onto your calves and train you to spring off the balls of your feet like a powerful cat! Special plyometric exercises help develop fast twitch muscle fibers in your legs for explosive leaping improvement! Used by slam dunk contest winners and top pro & college teams! DON'T MISS OUT! Smoke free, pet free home! Thanks for looking! Please contact me if you have any questions.