This Ball is wonderful as it assists the user in improving alignment, strength and coordination. Including this ball in Pilates workouts means promoting core stabilization by adding resistance, which forces users to engage and activate their pelvic floor muscles. Additionally, the ball is an unstable surface, which promotes deeper core stabilization. Because of its size, this ball is more than just a Pilates accessory. Squeezing the ball between the legs strengthens leg muscles and the buttocks. You can also bounce it and catch it to improve coordination and skills. So durable and so versatile, the ways this ball can be incorporated into wellness, fitness and mind-body exercises is nearly limitless. The ball arrives deflated but comes with a straw to aid with inflation. Fully inflated, the ball has a diameter of about 7", but users can inflate and deflate based on personal preference and need. With a weight capacity of about 265 lbs., this Togu Redondo Ball is suitable for nearly everyone. Please note, this is the Togu Grey Redondo Ball only. An inflation pump is not included. Not just for Pilates, this versatile ball also is terrific as a massage aid and as a neck rest. When inflating, press a finger next to the straw so that when pulling it out of the tube, less air escapes. Foldable, the ball is ridiculously easy to store and travel with. Deflated and carefully folded, the ball fits on shelves and in car trunks and travel bags. Not just good for your body, this ball is also good for the environment. It's made of 100% recycled plastic. Easy to clean needing just a damp, warm cloth and mild soap.