This 1941 booklet, measuring 3-5/8" by 8-5/8" of 40 pages, is a handy book from National Union Radio Corp. (Newark, NJ) listing over 600 types of radio tubes, charted by number, similarities, description, base connection, filament volts, amps and type, plate volts, screen volts, control grid volts, plate and screen current, amplification factor, mutual conductance in micromhos, power output in milliwatts, and load resistance in ohms. Also included is 7 pages of bottom views tube base pin connections.
Vital for the radio historian, collector, rebuilder, etc.
Item is very fine, no markings, creases, bends,
Item shown is one you will receive.
From a non-smoking environment.
I will combine shipping if multiple items of mine are acquired.