Firm Green * 14.5 X 8 X 1.75 Shipping Carton Size: 16 L X 12 W X 5 H *theraband Stability Trainer Is Used To Improve Motor Skills And Balance Particularly Among The Elderly And For Knee Back And Ankle Rehab * Two Foam Pads Of Different Densities And One Air Filled Cushion Allow Users To Work Through Progressive Levels By Standing On A Pad * The Green Stability Trainer Is Firm And Provides A Beginning Level Of Challenge * The Blue Stability Trainer Is Soft And Introduces An Increased Level Of Challenge To The User * For Maximum Challenge Use The New Extra Soft Black Stability Trainer. It Is Air Filled To Provide Multiple Direction Displacement * One Side Offers Rounded Points For Sensorimotor Stimulation And Its Heavy Gauge Side Walls Resist The Tendancy To Roll The Ankle During Exercise