The ball plunger can be activated from any direction within 360 degrees, using a sliding motion such as that produced by the opening or closing of a door or window into its frame. But they also have been used very effectively as an interior trap device by mounting on a flat surface, such as a display table, and placing the protected object directly on the switch to conceal and actuate the roller ball. GRI Roller Ball Switches can work when nothing else will. Spacers and mounting hardware included with switch and also available separately. The terminal version is indicated by the addition of "T" after the part number.