Green light is especially useful in sharpening outlines. The human eye is most sensitive to the green range of light, it's the brightest of all the colours but this also makes it easier for others to see you. For self protection it provides an added glare effect and is invisible to wild animals. Green light also does not attract insects like white or yellow light does. It is also useful in smoke or fog filled environments.
Red light is generally used for protecting your natural night vision. Used by aircraft personnel, the military and hunters to avoid spooking game, deer and other animals that see very poorly in the red colour spectrum, also ideal for fishing as it attracts young fish and does not reflect off the water surface. The filter is also useful for close range, non-tactical applications such as map reading as it reduces the intensity of light output. However, it is close to infra-red band so an enemy with a night-vision device has a better chance of seeing the "hot-spot".
✔ Contractile TPU lens come to ensure the filter fixes securely on the flashlight.
✔ Lanyard hole design, make the filter connect to flashlight through the lanyard
✔ Olight D40-R or D40-G Filter *1 (either red and green depending upon your selection)