Perfect size for everyone Large 27.5cm size so you don't have to worry about not using the board and slipping during training. An anti-slip groundsheet provides additional protection for the board and the floor.Material: Polypropylene (PP) resin, non-toxic, odorless, tasteless, safe and durable.Effect: Spiral fat burning method, ten minutes a day, hold slim waist, legs, buttocks, eliminate fat, form a perfect curve, can exercise at home.Strengthen your abs and core: You will feel stronger in your abs and back if you continuously train them by simply twisting and turning them. And ultimately, you'll have more toner and a stronger stomach while you exercise.High Quality Craftsmanship: Each Twister training board is made of high quality plastic with a textured, non-slip surface for added safety. We've designed our spinning workout board with a balance board bottom, precision ball bearings, and foot massage nubs that allow waist twisters to spin smoothly on the spinning platform while enjoying the foot massage.