Buy Jump Ropes Quad Speed Cable Jump Rope Super fast jumping speed of 5-6 jumps a second Easy to change lengths with Philips head adjustable screw/collar Comes with a choice of 10' USA made nylon coated cable (bare cable is available) Ideal design for double unders or speed jumping; Ball-bearing handles designed specifically for comfort and control A popular rope in Crossfit Centers and jump rope competitions; 10' length is long enough for athletes 6' 6" (Using Proper form) Recommended for indoor use only; We recommend using the Jump Rope Fitness Mat if jumping outdoors