A security panel system that is adapted to protect innocent bystanders from gunfire in the event of a shooting. The security panel system includes a main body having a first rail, a second rail, a panel, and a locking mechanism. The first rail and the second rail may each be mounted adjacent to a window and movably secure a panel therebetween. The panel is movable between an opened position and a closed position. The locking mechanism is configured to secure the panel in the closed position. It should be appreciated that, while the panel is in the closed position, the shooter may not be able to see or fire through the window due to use of the security panel system.

A door opening/closing device includes: an opening/closing bar attached to a door, which is actuated by a motor and is used for opening and closing the door; a door closing state detecting part configured to detect whether the door is in a closed state; a locking device configured to lock and unlock the door; a lock pin capable of being moved to a locked position or an unlocked position by the locking device; an engaging member attached to the opening/closing bar, which includes an engaging part configured to engage with the lock pin moved to the locked position; a first spring provided between the opening/closing bar and the engaging member; and a locking control unit configured to cause the locking device to lock the door when the closed state is detected by the door closing state detecting part.

Exemplary embodiments include an electromechanical lock configuration for use in locking, particularly curtain type doors typically used to close garage spaces but also used for closure of industrial and commercial spaces for alternative purposes. Aspects of the electromechanical lock configuration may also find applications in locking of other closure doors or panel members whether they be of the curtain door type. The electromechanical lock configuration includes a latchable restraining mechanism that includes a latch bolt assembly having a linearly movable latch bolt movable between a withdrawn position and an extended active position that restrains the door or closure from moving from the closed position. The latch bolt assembly includes a selectively operable electrically activated latch drive for moving the latch bolt between a withdrawn position and an extended active position through a drive gear. A manual override is also included.

Fenestration units including a movable sash located within a fenestration unit frame are described herein. The fenestration units further include structures configured to retain the movable sash within the frame with the structures being configured to form mechanical interlocks with the fenestration unit frame when the movable sash is in a closed position within the fenestration unit frame.