This ball is the best way to improve your flexibility, relieve muscle tension, strengthen the pelvic floor muscles and stretch the whole body. The durable material makes the ball comfortable and easy to use, and it can just as easily replace a chair at the computer, allowing you to sit comfortably without back pain. The package also includes a pump that fits exactly on this exercise ball. The colours are supplied assorted. It is not possible to choose a colour. The price is per ball.