The Olight blue filter creates a soft blue light that provides a less disturbing light, good for navigation and map reading. Provides more light than other filter choices while still reducing light output for tactical applications. Hunters use the blue filter to track wounded game at night because blood stands out more distinctly against foliage when viewed under blue light. Fits all Models of Olight M30 Flashlights. Uses a high quality TPU body construction that offers flexibility and durability, as well as chemical and abrasion resistance. Lens features a top quality anti-reflective coating on both sides for optimum light transmission. Includes a lanyard loop for portable and storage convenience.