The Norton 8501-H-689 Surface Mounted, Aluminum Finish Friction Hold Open Door Closer Multi-Size 1 thru 6. The 8501-H-690 Closer Is A Grade One Surface Mounted Commercial Door Closer Hold Open Achieved by means of friction or ball and detent/ roller. The Norton 8501-H Friction hold open has a range of 90° to 180° using template location and mechanical adjustment. Norton 8501-H Hold Open Door Closer with Slim Line Cover For Use In High Traffic Areas In All Types Of Institutions, Hotels, Factories, Healthcare, Ect. Norton Door Controls 8501-H Friction Hold Open Closer arm, Aluminum Finish Door Closers Are Manufactures Of Quality Made Commercial Door Hardware. See Spec Tab For Additional Product Info.