Long hinges like these are sometimes used on the back of wood boxes, or maybe your trunk is in rough shape back there so you need a hinge that attaches in many locations. Here it is. These are called Piano Hinges and are made of nickel-plated steel. Overall length of this hinge is 21 and 1/2 inches. Overall width, when opened flat, is 1-1/2″,
and there are holes for your fasteners every 2 inches across each leaf of the hinge.
Sold one at a time, or ‘By the Each’ as we say in Maine. HNG-17 Piano Hinge, $12 each, USA shipping included.