A latch bolt in the rim of the active housing engaging an adjustable roller strike provides the locking action. Depression of the crash bar GÇ£unlocksGÇ¥ the device and permits egress. The bolt reengages the strike and locks when the door closes. On single doors the adjustable strike is mounted on the frame lock jamb. The adjustable strike is an integral part of a removable mullion which is required for pairs of doors. The exit device can be deactivated or GÇ£doggedGÇ¥ with the cylinder key or Allen key. Keyed alike cylinders are optional. A standard rim type cylinder of 1-5/32" (29.4) diameter is required.