This CRL Jackson® Regular Duty Extended Spindle 90º Non Hold Open Overhead Concealed Closer Body features a 1-13/64" (31 mm) long spindle, the preferred length when used in conjunction with patch fittings and rail hardware. Standard dual action valves for closing operation (one valve for closing, one valve for latching). 90º and 105º Hold Open and No Hold Open models are available. Closers fit into standard 1-3/4" x 4" (45 x 102 mm) or larger header extrusions. Interchangeable with all Jackson® and similar brands of Overhead Concealed Door Closers. Important Notes: Closers set to comply with A.D.A. specified opening forces might not provide adequate spring power to control and close the door due to varying site conditions and door size. Mounting clips are not included with this closer body. Unless the existing mounting clips are used, you will need to purchase the appropriate clip package for your application. Contact Jackson® Technical Sales Department for assistance in selecting the correct Mounting Clip Package.