Use the 66fit Wooden Balance Board for a speedy recovery and return to sport. Using the 66fit Wooden Wobble Board post injury will allow you to regain and retrain your sense of balance (proprioception) and coordination and help strengthen weakened muscles to accelerate your recovery so that you can return to the sport that you love quickly and safely. The 66fit 50cm board has a gentle 12 degree angle tilt making it the ideal choice for beginners and intermediate users to progress through the early to middle stages of rehabilitation following an accident or injury. The 66fit 40cm board has an acute 16 degree angle tilt and small sized wooden ball at the base making it a difficult and challenging piece of rehabilitation/ exercise equipment. With this in mind the 40cm size Wooden Balance Board is recommended for intermediate to professional use only. Please Note: Take care when using on tiled floor to avoid slipping. Preferably for use on a padded floor mat/ carpet etc for added safety.