Navaja Knife | Doppler Phase 4 (Navaja P4) was added to the game on March 13, 2019, alongside the "Seeing the Light" update. The skin is available in The Prisma Case.
The blade and the front part of the handle are painted with metallic paints and adorned with a pattern of translucent wavy lines resembling smoke. The color scheme of the skin uses various shades of blue, brown and black creating gradient transitions. The main part of the handle remains unpainted
Float Value of the skin ranges from 0.00 to 0.08, which makes Navaja Knife | Doppler Phase 4 available only in Factory New and Minimal Wear condition. At levels of wear close to the maximum, the knife has noticeable scratches and abrasions located on the spine and the front part of the handle.
The pattern index affects the ratio of colors as well as the location of blue, brown and black areas. Pattern variations with a predominance of blue on the play side of the blade are titled “BTA Blue”. Knives with only blue color on the blade resemble Navaja Knife | Doppler Sapphire and are titled “Max Blue”.
The quality of Navaja Knife | Doppler Phase 4 is Covert. The skin has a StatTrak option and is close to phases 1 and 3 in terms of rarity. The skin belongs to the "Navaja Knife | Doppler" series.
“Doppler Phase 2” is one of the most popular skins for M9 Bayonet. The skin has a very large number of fans and is considered to be more valuable than phases 1, 3 or 4.