Closers for interior and exterior doors shall be full rack and pinon type with cast aluminum alloy shell. closers shall be surface mounted and shall project no more than 2-7/8" from the surface of the door. closers shall be non-handed to permit installation on doors of either hand. Closer fluid shall contain lubricity and anti-oxidation agents. Closers shall be sized for each door. Closers shall have two non-critical valves to independently regulate sweep and latch speed. Closers shall have adjustable backcheck. Regular arm and top jamb closers shall have a non-hold open shoe permitting 15% (+/- 7-1/2%) power adjustment. [9300BC].