Use extra lines for the movement they control
Check the primary rack straps first, then identify whether the bow or stern can move fore-aft or lift in wind. Choose approved anchor points and keep the lines clear of paint, sharp edges, hood seals, wipers, and moving panels. Recheck after a short initial trip.
The Bing cluster includes a question about leaving a kayak on pads overnight and other transport variants. These are related but not interchangeable: parked storage, highway travel, and an anchor method have different boundaries.
Limits
No kayak, rack, vehicle, line, wind, or speed was tested. This guide does not approve a particular anchor point.
Sources and related reading
See Also
If you want to move from general advice into actual product choices, start with Can a Kayak Stay on Crossbar Pads Overnight?, Loose Roof Rack Noise: A Torque, Bar, and Fairing Diagnostic, and Tonneau Cover Drain Hoses: Route, Sag, and Blockage Checks.
For a wider picture after the basics, Best Truck Bed Mats for Grip, Bed Protection, and Exact Fit and Extang Trifecta 2.0 Tonneau Cover Review: Fit, Features, and Trade-Offs are the next places to read.