Under the threat of nuclear war in the 1950s and 60s, Americans prepared for what life might be like if they survived an attack. The dosimeter is a pen-size scientific instrument with an eyepiece you look into at the top of the dosimeter and a charging contact at the bottom. Inside the device is a microscopic scale with a hairline indicator. This shows the amount of radiation absorbed by the device since the last time it was reset to zero. The dosimeter is reset by charging it with electricity using with a dosimeter charger. This instrument measured the amount of radiation (roentgen) that objects might have. This CD V-742 was a direct-reading (self-reading) pocket dosimeter that measured exposures from 0 – 200 roentgen (R). The CDV-742 can be identified by its bronze or gold colored pocket clip. The CDV-742 high range dosimeter is the standard for use in shelter, WER [Weapons Effects Reporting] Stations, emergency service organizations and vital facilities. They would also be used by the millions of civil preparedness workers that would be needed for recovery operations during the postattack period when emergence from shelter is possible. It measures 4.25' long and 0.5' diameter.