Adjustable ParallettesTake your calisthenics, gymnastics, and functional workouts up a notch with these adjustable height parallettes. Engineered for total stability movement, they adapt seamlessly to your training goals. Whether you're indoors or outside, you'll feel the differencein your form, control, and comfort. But be sure you train on a firm, level surface. Do not use on soft or uneven ground (e. g. grass, sand, carpet), as this may cause tipping or injury.