The S77 treadmill offers the power of a fitness club quality treadmill in the comfort of your own home. The S77 incorporates the same great features as our best-selling F85 treadmill, features the largest deck of any SOLE treadmill. The S77 treadmill’s automatic incline adjustments in heart training mode help keep users exercising within their target heart-rate zone, while the included wireless chest strap boasts a 99.9% accuracy rating.