Where pickup trucks sell well, a popular OEM and aftermarket option is the hard tonneau cover, which encloses the pickup box, providing dry, lockable storage for contents. Tonneau covers also improve drag coefficient by reducing turbulence in the bed — a highly desirable feature on vehicles notorious for their poor fuel-economy ratings.
Traditionally, hard tonneau covers have been produced via spray-up fiberglass (with an unsaturated polyester matrix), although, more recently, compression-molded sheet-molding compound (SMC) and thermoformed monolithic thermoplastic sheet have also been used. Unfortunately, each of these technologies has had its problems.
A new sandwich-panel composite developed by Penda Corp. allows the company to produce the lightest hard tonneau cover in industry and the first OEM tonneau cover with MIC body-matched color
Both fiberglass and SMC tonneau covers are heavy enough to offset much of their aerodynamic benefits. High mass makes it difficult or impossible for one person to install/remove a cover alone.