Best Jump Rope for Boxing - Martial Arts - Crossfit - Kids and Adults - 10 FT Adjustable Cable - Nylon Travel Bag - Great for Weight Loss FOR KIDS AND ADULTS - The ThunderJump speed jump rope is your best choice for stunning Crossfit training, WOD's, Martial Arts and MMA training, Boxing, Bodybuilding, Professional Athletes and Personal Training. SLEEK, LIGHTWEIGHT, DURABLE HANDLES - Made of Polypropylene (PP), a tough thermoplastic polymer, ThunderJump handles are highly heat and cold weather resistant, so you can crush your WODs all year round. Its also resistant to fatigue and has excellent impact strength and stability, which means your Thunderjump rope will keep on working as long as you want. The modern, tapered design offers the feel and comfort you need when doing ultra fast double-unders! DOUBLE BALL-BEARING DESIGN - Unique double ball-bearing system design to achieve maximum spin, with control and precision. Attached at the head of the handle is a matte black spindle rod, equipped with a standard rolling-element ball-bearing, to ensure a kink and tangle free performance. An additional spherical bearing at the end of the rod end gives an added element of speed and accuracy required to do double-unders. 100% MONEY BACK GUARANTEE - ThunderJump speed jump ropes are backed by a no-questions-asked money back guarantee. If you are not 100% completely satisfied with your purchase, we will replace or refund your order.