The Star Trac 4000 treadmill is for fitness enthusiasts who want the best-of-the-best: that is, the top-of-the-line model from the world’s top treadmill company. What makes it so special is a collection of attributes not found on basic running machines. It starts with the impact-absorbing neoprene deck cushion and ’soft-system’ levelers that will bring bliss to your knees, hips, and back as you run (patented Impact Absorption System).