Inner Dimensions: 12" X 18 3/8" 

Outer Dimensions: 13" X 19 1/2" 

The clamp ring for this window is sold separately.

Please Note*** PLEASE MEASURE YOUR WINDOW AND COMPARE TO THE DIMENSIONS ABOVE. The dimensions shows with the part numbers are just the outer dimensions. Please measure Inner and Outer dimensions. Measurements can vary by 1/4".

‍There are discounted windows in this size available. These windows may have:  scuffs, dents in frame, scratches, screen damage, etc.  All damage is minor and the windows are still functional.  These are sold AS IS and are non-refundable.