Don't know why, perhaps due to rising demand and production bandwidth, but be forewarned quality control is an issue. Assembly is easy enough, though have gap where back separator does not fit snugly after tightening nuts as firm as they will go (see pic). No water level sticker on tank received, so had to measure water manually according to calculations (4 gallons). Siphon was not air tight (even though release valve closed firmly), so had to manually pump instead of siphon. S4 monitor only flashes, not working as of yet and now have to take a apart top of unit to figure out why, currently not resolved after verifying connections and looking at simple solutions on website.
Outside of resistance type, we found the number-one arbiter of ride feel to be cord quality. Water ergometers tend to employ nylon cords, while air ergometers feature metal chains — a durability factor we anticipated would result in our favoring air. But while all three water rowers aced our expectation of smooth, high-tension strokes, perfecting the chain seems to be more difficult: Some tug with just a slight rumble, others feature bouncy, grinding chains that are incredibly loud, something akin to angry snoring. As for nylon, the best wind and unwind like elastic silk — no slack, no sound, no catching, just perfectly even tension throughout the stroke.
Other details include dual rails with four corner wheels that increase seat stability and reduce the amount of sweat buildup; a frame that flips upright for handy storage; and a weight capacity of up to 1,000 pounds. The WaterRower Natural measures 84 by 21 by 22 inches (W x H x D), weighs 117 pounds (with water), and carries a one-year warranty on the frame and components (WaterRower will upgrade the warranty to five years on the frame and three years on the components with the completion of a registration form).
As with any fitness activity, it’s important to exercise with proper technique, however. The big muscles in the legs are where most of the workout action should be. Injury to the lower back can occur from bending too far forward in the row. It’s best to maintain a upright 90 degree angle to the rowing machine’s seat and slider bar. Using the legs for the motion rather than relying as heavily on the back or arms can help reduce the chance of muscle pulls or other related injuries. Always check with a physician before starting any new fitness regimen.

The WaterRower Natural is outfitted with a Series 4 performance monitor that's designed to balance technical sophistication with user-friendliness. The monitor--which includes six information and programming windows, six QuickSelection buttons, and three navigation buttons--displays your workout intensity, stroke rate, heart rate, zone bar, duration, and distance. Plus, the monitor is compatible with an optional heart rate chest strap and receiver, which helps you optimize your workout and achieve your exercise objectives.
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