4 3/8" wide x 11 3/8" long x 3/4" high (7/8" neck). Installation hole size: 3 1/4" x 10 1/4". Predrilled with six mounting holes to accommodate #8 screws. Louvered vent is made from 304 stainless steel with highly polished finish. All-welded construction. Adapts to 3" or 4" ventilation systems.