Anton Model 201 End Window GM Tube (1950s)
An advertisement in the September 1950 issue of Nucleonics describes the Anton Electronic Laboratories, Inc. Model 201 end window GM as an "advanced GM counter developed for U.S. Navy."
With regard to the tan colored ceramic insulator, the advertisement states: "A basic improvement over conventional flame-worked glass bulb: Precision molded… uniform diameter… accurate alignment… mechanically stronger. Deep grooves lengthen surface path to minimize external leakage. No bulge around cathode to interfere with probe assembly or restrict stacking…no wax coating to be scratched… and non-photosensitive."
"Located in the center of research activity, in New York City, cooperating with eminent scientists in many fields, the ANTON Laboratories provide completely integrated facilities for research and production. We design what we make—and make what we design."
Size: 5" long and 7/8" in diameter
Wall: Stainless steel
End window: Mica, transparent probably 1.5 mg/cm²
Gas: Halogen quenched
The Anton 201 was sometimes used in the military's AN/PDR-27 survey meter instead of Electronic Product's 5979 tube. Believe it or not, a modern version of the Anton 201 is commercially available, the LND 722 (thanks to Richard Hull for this bit of information)!
Reference
Nucleonics, advertisement, September 1950 page 89.