Armstrong Performance Foil MastArmstrong Performance Foil Mast These masts are designed with a mast rake angle. This fine tunes the board angle relative to the foil for a more comfortable and forgiving ride. It does not change the lifting force or balance of the foil itself, and it does not impact the foils foot pressure bias front or back. Board rocker also directly determines effective mast rake boards from different brands have a variety of different rocker lines which influence