Improve balance, coordination, strength and flexibility of knee, ankle and leg muscles and ligaments Each balance board is 20” wide for a stable stance and has two adjustable spheres to vary difficulty Single-plane of tilt (10, 12 & 15 degrees) pitches back & forth, and is adjustable based on ability Constructed from durable Baltic birch plywood that helps to improve core strength and body awareness Perfect for balance training, physical therapy and rehabilitation from knee, ankle and leg injuries