At the first sign of trouble outside, lock down a classroom instantly with MARKS USA’s Loc-Down™ Intruder Locksets. Typical Classroom function cylindrical locksets are designed to be locked or unlocked from the exterior with the interior always in an open position, but allows in emergency life safety situations the teacher to secure the classroom without stepping into the hallway to lock the outside handle. Faculty & students remain safely within the classroom. There is no need to open the door; the exterior lever is disabled by operating the interior lock cylinder.
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