The first Precor Ellipticals - the Precor EFX 544 Commercial Series, and the Precor EFX 5.21s, 5.17, and 5.21si Home Versions - incorporated all the technology you still see today. Precor then introduced the famous commercial series EFX 546 elliptical, and commercial EFX 556 Elliptical with Moving Arm technology. Meanwhile, in 2002, Precor introduced a full line of Home Version Ellipticals - The Precor EFX 5.17i, 5.19, 5.21i, 5.23, and 5.33 Ellipticals. Precor has continued to stay ahead of the game and more recently introduced the Commercial 576i Elliptical, which combines both its famous Moving Ramp Technology and Moving Arm technology. And more recently, Precor invented the award winning AMT Adaptive Motion Trainer, a machine similar to an elliptical while allowing for a more user defined movement. Checkout our comparison charts on Precor Home Version Ellipticals to help you find the right Precor Elliptical.Click to shop for Precor Elliptical Crosstrainers...