The StrechCordz Modular Set is an exercise machine in a bag.áThe Modular set is a complete wet or dry-land swim training tool that can be used for pulls, rows, raises, curls, flies - nearly any resistance exercise you can imagine. The StrechCordz Modular Set comes with a carry bag which includes one pair each of interchangeable handles, paddles, adjusting leg straps, mounting straps and two 4ft/1.2m tubes. Interchangeable. Replacement and additional parts available. Available in five resistance levels. The Red resistance has 12 - 31 lbs of resistance.