After the Sino-Soviet split in the early-1960s the Chinese government began to develop its military industry so it could develop its own military equipment without the help of exports from the Soviet Union. As part of this, in late 1964, the Chinese military moved to design a new, gas mask for the People's Liberation Army. They eventually designed what would become the M65.
The mask uses a very unusual and awkward one sided cheek filter located on the left side of the mask. The mask's filter is a large egg-shaped filter that is molded into the mask, rendering it irreplaceable, and rendered usable for no more than one to two occasions before replacement was necessary. The M65 has two tissot tubes running underneath both lenses with a small hole on the side facing the nose and mouth to let air flow directly through to the mouth and nose, while eliminating lense-fog all at once. Due to this, the mask utilises no oral/nasal cup to prevent fogging. It uses a seven-point head harness (one strap runs to the back of the filter to hold it close to the users head) and is made of a highly elastic fabric with easy to adjust buckles, having both a forward and rear adjusting straps, with a padded leather and fabric triangular shaped head harness pad.
The lenses are oddly shaped, resembling small, rounded, angular triangles, with galvanized tin rims. It uses a combination of an exhale valve and voice diaphragm in one assembly. There is a small ring that goes into a large opening on the front of the mask (covered by the plastic threaded voice/exhale valve cover) that has a small, turquoise colored piece of rubber that magnifies the wearer's voice, and small oval cutouts around the outer plastic edge that a thin rubber ring covers, which is the exhale valve.
The mask is made of a very soft, and comfortable off-white colored rubber. The head harness and rubber makes the M65 a very comfortable mask to wear for extended periods of time. The mask also comes with a small dark tan container that contains anti-fog inserts and their plastic locking pieces, along with a replacement exhale and voice diaphragm rubber. The cover for the inhale port on the filter case has a molded in communist star, denoting it as a Chinese gas mask.
The mask's haversack is very small, measuring around 7 x 7 inches (17.8 x 17.8 centimetres) and has a small pocket in the bottom for storing the small container. The haversack strap is very oversized so it will fit comfortably on any size and shape of body. The masks will come packed in a plastic bag with the size marked on the outside (sizes 1-2). There are two versions of the mask, the early version which has the exhale valve, and filter inhale cover sealed with tough rubber bands, and a later version has the more common metal clamps with snaps.
The mask itself saw limited use in the PLA, and so most have been stored very well and are in excellent shape. China instead sold large numbers of them to the North Vietnamese Army (NVA) and the Vietcong (VC), who used them throughout the Vietnam War.