Retexture of the HGU-55/P helmet to grey in addition to a retexture of the MBU-12/P oxygen mask to the MBU-20/P. This combination is most commonly found with foreign operators of the F/A-18 such as Australia, Canada, Finland etc.
Also included is a standalone retexture for the mask, keeping the reflective white helmet for US Navy operations.
These textures won't work if a particular skin is using a unique helmet texture. Included is a single layered .PSD to add the oxygen mask to the unique helmet texture if you so desire.