Bestop 15145-01 ZipRail Truck Tonneau Cover for Nissan Frontier, Crew Cab, 4.5' Bed, 1999-2004 Leather-grain premium vinyl/polyester fabric stays flexible in cold weather, features limited lifetime warranty Proven BeltRail attachment system features quick-release tabs, variable-position clamps for no-drill install Aluminum bows span across truck bed to support the tonneau, help prevent puddling Easy access to truck bed and cargo by simply dropping tailgate or by pulling up the cover Limited Lifetime Warranty