Ready for a very stable, ultralight, dual pocket 21 oz hydration handheld? We are! We stabilized the movement by encasing the bottle in a semi-rigid shell, then added an extra wide strap for comfort and torsional stability. Reflective webbing on the bottom keeps you visible and per many requests we designed the elastic dual pockets so that you can fit in iphone and most droid phones. BPA free 21oz bottle included.