Invacare® raises the bar of power wheelchair driving performance by introducing G-Trac™. G-Trac™ improves the performance when added to the ACS II Control on Invacare®’s Storm®4, FDX®, TDX® SP and Spectra® XTR models by working like an electronic compass. This mechanism makes tracking performance and traction better. G-Trac™ improves control at any speed - faster outdoors or slower indoors. Safety and comfortable are intact with consistent driving performance.