RopeFit Heavy Jump Rope Hand crafted in the USA Made with the highest quality, rugged, poly dacron rope, but soft exterior so won't damage gym mats like cable Heaviest Rope Available.1.5x9=4lbs 1.5x10=5lbs.2x9=7lbs.2x10=8lbs If you're under 6ft tall we recommend the 9ft rope. 6ft or taller we recommend the 10ft rope Strengthens the shoulder/rotator cuff and increases flexibility