As tensions during the Cold War arose, a new type of mask design was introduced with the filters being inserted into cheek pockets on both sides, as opposed to using a canister on one side. The first to go through with this was the M17 series, developed in the late 1950s. Since the filters are properly seated, this ensured that it wouldn't be able to cause any leaks, thus preventing the wearer from becoming compromised to contaminated air particulates. These masks were lighter in weight compared to their canister counterparts, and some featured a voice diaphragm, as well as a drinking tube, (most notably with the M17A1 variant). However, their filters didn't last as long as the standard canister. They were also difficult to replace, but were generally liked among most soldiers in the US Military.
The majority of these masks remained in service for a long time, from the mid 1980s to the late 90s, most have been replaced by their much more simple and more practical canister filter masks. (i.e. US M40, Russian PMK.) However some are still used today for riot control purposes, or industrial use.
It's worth noting that countries such as Czechoslovakia, Poland, Bulgaria, and Russia in particular picked up on this design.