Step-by-step installation of a BakFlip MX4 tonneau on a 2014 Toyota Tundra. I installed the BakFlip deck rails with adapters to accommodate the OEM accessory rails. The matte black, trifold aluminum cover holds up to 400 pounds. Okay, that's impressive but I don't plan on hosting any disco marathons on top of the cover or stacking a bunch of stuff a la Beverly Hillbillies. I'm more concerned about how it holds up in rain...a bunch of Florida apocalyptic rain. A review follows.