Fitter Rocker & Wobble Boards feature beginner, intermediate and advanced movements. The beginner Rocker Board is designed for single plane movements and has a maximum angle of 14 degrees. Intermediate Wobble Board features adjustable tilt angles of 10, 12 and 15 degrees as well a 360 degree range. The Advanced Wobble Board, features adjustable tilt angles of 15, 17 and 20 degrees and has a 360 degree range. A Five-inch polyurethane hemisphere spins off easily to accommodate a spacer that varies the tilt angles of the Wobble Boards.