Say good-bye to boredom once and for all: a few simple moves is all it takes to convert the 4D PRO® sling trainer into 4 highly versatile training tools.
This product will provide you with a resistance expander, an elastic rope, a conventional non-elastic sling trainer and a dynamic sling trainer that offers lots of elasticity.
United States Ski and Snowboard Association
University of North Carolina
Delaware Swim Team