All metal body construction for added durability|Size 3: works with doors weighing less than 125lbs.|UL Listed: 3-hour fire rated for added protection and meeting building requirements|Interior doors: Left or right hinged doors up to 125 lbs. and 38" wide|Exterior doors: Left or right hinged doors up to 125 lbs. and 30" wide|Adjustable closing and latching speeds eliminate door slamming|Opening range: 180-degree for added convenience and pass-through space|Mounting: Standard, top jamb or parallel mount