Description: Material: This Yoga Ball Chair is made from PETG material, ensuring sturdy and safe.Design: The chair is blow molded for a lightweight and easy to shape texture. It features an ergonomic backrest, a heightened front baffle, and imported omnidirectional wheels for maximum comfort and mobility.Feature: This yoga ball chair effectively improves posture, adjusts body shape, corrects sitting posture, coordinates the spine, strengthens core exercises, enhances body coordination and promotes a training back. It's suitable for yoga practice and fitness routines at home or in the office.Easy Installation: Simply insert the chair bracket into the base slot of the chair; tighten screws at the bottom of the chair; push omnidirectional wheels into small holes at base until locked in place; place yoga ball on top to use.Product Details: The chair with dimensions of 52cmx79cm for yoga ball seat suitable for individuals between heights of 155cm to 175cm. Specification: Material: PETG Size Chart: Chair:52cmx79cm/20.47inchx31.10inchSuitable for height: 155cm to 175cm/61.02inch to 68.90inch Package Includes: 1 Yoga ball seat1 Backrest4 Omnidirectional wheels2 Screws Note: Please allow slightly errors 1-2cm differences due to manual measurement.