2 x AAA Batteries (not supplied) On/Off – Press and hold the power button for 3 seconds. V – Volume – Scroll through the 6 volume settings including a silent mode. S – Sensitivity – Scroll through the 5 options. By depressing the S button the L.E.D will flash with accordance to the sensitivity level selected. N – Night Light – Press and hold for 3 seconds and the green night light is activated/ De-activated. L.E.D Multi Colour option – Press and hold simultaneously both buttons. The alarm will automatically scroll through the 4 x L.E.D colour options release on the selected colour of your choice.