Background
Classic sports car snap-on tonneau cover
Tonneau covers, from the French word for barrel, were invented over a hundred years ago to protect rear passengers in open air vehicles; the material was often draped in a manner resembling a barrel and the word stuck. Early race cars used tonneaus to smooth out air flow over unoccupied passenger seats, while sports cars adopted them in lieu of soft or hard tops.
Truck bed tonneaus have evolved into more complex assemblies since they typically cover a wider area. Common styles today are
FABRIC – snaps on the truck bed rail caps secure a single piece of cloth or vinyl which is folded up when not in use
ROLLUP – a fortified rib-like structure that keeps cloth or vinyl taut and is stored rolled up at the front of the truck bed
SLATS – aluminum slats, covered with vinyl, roll up and when extended down form a hard working surface
RETRACTABLE – a lockable segmented permanent hard cover that folds or retracts in some manner
STRUT – a lockable single piece permanent hard cover that opens much like a hood with strut supports
There are many manufacturers of “structured” truck tonneau covers (that is, all styles except the simple snap-on) designed to fit OEM truck beds.
