This CRL/Jackson® Extra Light Duty 1-13/64" Extended Spindle 90 Degree 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). 90 and 105 Degree Hold Open and Non 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 Closers.