... : 15cm, 20cm, or 25cm fitness step,aerobic step,stepperThree adjustment heights of: 15cm, 20cm, or 25cmSnap in legs for maximum stability Dimensions: 98*38 ... grooves for optimal traction and shock absorption Optimal length and width for Step Reebok moves Inclines and declines for body sculpting20GP: 500PCS40GP: 973PCS40HQ: 1141PCS aerobic step ...