The concealed 2010 Series is a heavy duty closer designed to provide complete concealment. The single lever arm and roller assembly provide smooth, quiet door control. The 2010 Series is concealed in the door frame with the track concealed in the door. The aluminum frame requires minimum 4"x4" tube for mounting. Featuring a cast iron body with a full compliment bearing, 1-1/2" diameter piston, 11/16" diameter double heat treated pinion journal. Select closer based on width of door. 2010 Series cylinders available in size 1, 3, 4, 5 or 6. Closing power of all 2010 Series closers may be increased 15 percent. Specify next higher size closer where strong drafts exist.