The official name for this proprietary technology is D.I.A.L.™, or Diode Illumination Adjustable Lens. Just choose the colour that'll serve you best and rotate the bezel to select:

• White - for general situatiosn
• Red - for preserving night vision
• Blue - for identifying fluids
• Green - for "be seen" safety and map reading (red makes contour lines disappear on OS maps!)

The tactile bezel is designed for use in dark conditions, making it easy to find the red light by touch alone. Powered by a single AA battery (included).

• Overall Length: 8.4cm
• Weight: 74g
• Lumens: 3
• Run time: 25hrs
• White/Red/Blue/Green
• Requires 1 x AA battery(included)