Since 1985, NZ Manufacturing has continued to improve and expand its extensive line of resistance exercise tools. We are extremely proud that our products are made in the USA from the highest quality materials. Whether you're on water or dry land, StrechCordz provide the best swim training products on the market. Improve your stroke, endurance and strength safely and effectively with StrechCordz. Athletes and swim teams all use StrechCordz for their training needs.