Part of the internal workings of a camera, the pressure plate is located on the other side of the film from the gate. It is a smooth, spring-loaded plate that holds the film on the film plane and acts as a brake, helping to hold the film steady while it is exposed.thepolliofolioglossaryofcinematographyterms
A smooth plate found on the inside of the camera back that is forced towards the front of the camera by springs, causing it to hold the film evenly in place for exposure.
When using a graphics tablet (a computer input device on which a user hand-draws images or writes text with a special stylus, just as you would draw using a pencil and paper), you can achieve different effects by increasing or decreasing stylus pressure.
Triggers responds to weight (being walked on, stood on) to open doors or activate surveillance camera trained on area. Placed in front of doors, gates and other entrances.