Stainless steel vent frame, part number 215538.  It roughly measures 26 1/4" X 4 1/2" at it's longest and widest points.  The inner cutout roughly measures 19 1/2" X 3 1/2" at it's longest and widest points.  The mesh insert roughly measures 22" X 4 1/8" at it's longest and widest points.  There are 4 mounting screws across the top that roughly measure from left to right: (1) at 8 3/4" each (1) at 8" and (1) at 8 3/8" apart, center to center.  There are (2) mounting screws across the bottom that roughly measure 7 3/8" center to center, from left to right.