Add a little kick to your bodyweight exercises! These Pro-Tec Resistance Bands are a great addition to your strengthening regimen, helping to keep your muscles strong. Consistent strengthening can reduce the risk of overuse injuries it should be a key part of every runner's weekly training schedule! All three resistance bands in this pack measure 24 x 2. The pack includes one light resistance band (.7 mm), one medium resistance band (.9 mm), and one heavy resistance band (1.2 mm). Each pack comes with a microfiber carrying bag and an exercise guide.