APS 2/2 50

APS 2/2 50 is a Polish firefighting breathing apparatus. Produced from about the 1960s to about 90 and used until about 2015. It was manufactured by Faser. The oxygen apparatus was used with the GSP mask, which unfortunately I do not have, so instead of that in photo 6 I used the SZm41m (OM14) mask

I bought the oxygen apparatus from a Polish youtuber recording about his collection of gas masks, whose channel you have in the links tab (Link No. 1)