The compact, low profile design of the ST740 features two adjustments to ensure proper ergonomics and biomechanics. The seat position places the user at the appropriate height in relation to the exercise arm, while the foot rest helps maintain a 90 degree bend at the knees. This unit has six different start positions to accommodate a vast array of range of motion preferences. The backrest is adjustable to provide support during the abdominal crunch and freedom while performing the back extension. The 2" diameter pull pin heads provide comfort when making adjustments.