Nuclear Corporation of America NU-TEC (early 1960s)
Any baby boomer should be able to tell you the inspiration for this nifty design. That's right, it looks just like a hand-held transistor radio! You have the dial (actually the range switch) for tuning in the station, and a silver grill over the bottom half of the case to cover a (non-existent) speaker. It even has a jack for earphones! Alas, the tiny plastic knob for the tuning dial is missing.
The NU-TEC was manufactured by Nuclear Corporation of America in Denville New Jersey. Quoting the only literature I have for this, a 1962 advertisement: "Pocket-size GM monitor at $42.95 provides non-saturating response over 4 ranges... 0 to 10/100/1000 mr/hr and 0 to 100 r/hr. Flat energy response from 80 KEV to 1.2 MEV. Transistorized; uses one mercury cell. Battery life - 40 hours continuous. Earphone and test source included.
Case: ca. 2 1/2" x 4 1/4" x 1 1/4"
Advertisement. Nucleonics, April 1962, page 97.