Big capacity, with 2.2L, meet your water need in sports. Safety,using environmentally friendly food grade materials, safe and non-toxic.durable,can withstand high and low temperatures, and will not leave odors and stains when used repeatedly. Ideal for outdoor sports like bodybuilding, playing basketball etc, also a nice choice for picnic, party and so on. Sealing,precise leak-proof design, upside down, no bumps on the outside. Make portable dumbbells water for busy woman/men. They are easy to carry and better manage your physical condition at all times. Professionally to choose the right level of difficulty for your workout.