This is a left side defroster duct for a 1947 to 1954 Chevrolet or GMC pickup according to other listings.  I have others that look different than this that also are supposed to fit that series of truck.  This one has a 1 3/4" inlet with 3/4" x 6 3/8" opening. It has a clip on one end and 7" across to the other fastener.  Check these specs to confirm this is correct for your needs.  Would welcome information as to what it fits.  Free shipping, usually same day.