Massive bakelite tube socket PL3-1PD-95 (ПЛ3-1ПД-95) was designed for a specific tube, but this tube socket is also usable for 6S41S, GU-29, GMI-6, GU-32 etc. The upper spring is easily removable, it just serves for the specific tube fixing. The four side metal sheets are riveted into the socket, however these are relatively thin and flexible, so after its removal or better an adjustment is the socket usable also for the 6S33S and 6S18S tubes. Color of the bakelite varies inside the shades of brown. Minimum service life: 15 years (without crossing any prescribed limits). New old stock sockets made in the 80's.