Docooler 40cm Fitness Exercise Gym Fit Yoga Ball Multi-use Indoor Fitness Training Swiss Ball Made of PVC material, safe and antiskid, durable and abrasion resistant. This yoga ball will help you build strength, tone your muscles, greatly increase your flexibility and improve your balance. It fits all ages people of different health. You can choose a variety of training methods as easy, funny and fashionable. It can effectively adjust your posture and make your figure perfect if you insist in using it for a long term. Great for your spine and back health, wonderful for adding focus and energy to your workouts.