We have a vintage folding boat/ stadium seat.  It is red textured vinyl with a medium blue on the metal.  There are 2 clamps that fold out to attach to a bench/boat seat.  It measures about 14 1/2" in W x 14" in depth x 15 1/2" in height when in a chair position.  When folded the dept is about 16".  It is in overall good condition with the blue paint on the frame being scratched showing through to the metal in a number of places (see photo).  The vinyl on the back of the chair back has a few marks.  It is almost 6 lbs.  .

Seat Boat or Stadium Folding seat Red Vinyl blue metal Vintage