The Norton 8301 Adjustable Surface Door Closer is a multi sized door closer offering a complete range of arms and a sleek minimal design suited for moderate to high traffic architectural doors. It is Tri-Style, meaning it supplied with screws, a bracket and a soffit plate to allow for regular, top jamb and parallel installation.This door closer allows for adjustment of door speed from the door's full open position to down to approximately 10 degrees from the closed position. The Norton 8301 door closer is suitable for use on fire doors and is supplied with a slim line plastic cover.