Raytomic Model 521 Geiger Counter

Made by Atomic Research Corp. I'm guessing at the Model # because that's whats on the meter. There are other Raytomic units with the same model number that look similar . The main difference is the carry handle. This one is unique. Stainless steel case for easy cleaning. Originally it used two 45v batteries and D cells. It has a AA used for meter dampening, used to cancel out normal background radiation. The GM probe contains a Victoreen 900v 6306 bismuth tube.