https://www.civildefensemuseum.com/cdmuseum2/radkits/cdv715.html The CD V-715 was the most widely produced of all the Civil Defense radiation instruments with a total of 567,457 instruments produced. As far as I know Lionel, Victoreen and Landers Frary & Clark were the only manufacturers of the CD V-715. Here are 5 examples of CD V-715s. From left to right at bottom of photo, Lionel Model 1, Lionel Model 1A,Landers Frary and Clark Model 1A. The top row in the photo, Victoreen CD V-715 Model 1A and Victoreen Model 1B. Yeah, I know, they all look exactly the same.The CD V-715 and CD V-717 are very high-range gamma radiation detecting instruments. THESE ARE NOT GEIGER COUNTERS! To see the detecting range difference between the CD V-715 and the CD V-700 click here. The CD V-715 is a high range gamma survey meter for general postattack operational use. The ranges of this instrument are 0-0.5, 0-5, 0-50 and 0-500 roentgens/hour. When properly calibrated, the response of this instrument is within the range of plus or minus 20 percent of the true gamma radiation dose from a Cobalt 60 or Cesium 137 radioactive source. This instrument was designed for use by radiological monitors for the major part of their operation in the period following an attack. The instrument is primarily for surface monitoring survey but it can serve as supplemental equipment for aerial measurements.

Requires D battery