Rated Voltage: DC12V, DC24V(preferred) Button movement: 0.25-0.8mm Max button movement: 1.5mm Button contacts: 1 normally ope FeaturesFace plate of ... of 2~3mm thicknessCharacter: Landing Call Button, Up and Down Direction Button, Open and Close Door Button, Alarm Button, Intercom Button, etc.lighting colors selectable: ruby ...