The Sensorbox v2 shell has a button on top that interacts with a microswitch on the PCB. the original design did not work in my build, likely due to my use of a touch screen. 

This model is a modified version of the Sensorbox v2 Shell r3. The only modification is the addition of material on the lever that interacts with the microswitch, allowing the switch to be compatible with (at least my) "SPI TFT LCD 2.8 Inch Touch Panel" screen.