Are these kayaks recommended for whitewater use?

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No, Lifetime Kayaks are not intended for use in whitewater. Slow moving rivers and riffles are all right, but our kayaks are not rated on the whitewater I-V class rating scale.  Whitewater kayaks are made with a different design to handle waves, holes, and other features.  Lifetime Kayaks are recreational in nature and are not intended to be Eskimo rolled like a whitewater kayak. 

Recreational Kayaks are intended for flat water such as lakes, ponds, bays, and calm oceans.  Slow moving rivers and creeks are also approved as long as they do not have swift currents or rapid features.  Recreational kayaks are designed to be extremely stable and will most likely have keel or tracking channels to help with speed.