Bial EX Static Strength Exercise Stability Ball with Pump Balance ball rated up to 330 lbs, Includes ball pumpColor random The diameter of the inflated:55CM(21.6in). The essential element of an effective fitness & weight loss regimen - Tone your core, abs, gluts, hips Made of eco-friendly, phthalates & latex free, non-toxic materials - Safe for you & the environment! Anti-burst yoga ball can improve the balance ability and be used in rehabilitation training.