1961 Arvin 61R13 / 61R23
Shirt pocket radio, thermoplastic cabinet
4 1/4 x 2 13/16 x 1 3/8 inches / 108 x 71 x 35 mm
Six transistors (2N94, 2N194A, 2N233A, 2x 2N1059, 2N1251), superheterodyne circuit
One tubular 9-volt battery
Manufactured by Arvin, USA
The classic Arvin "Check-mark" radio: a late-model "Made in USA" set, though the electrolytics look to be Japanese-made. And as any transistor radio collector knows, you can always tell an Arvin's production/distribution date by its model number: the first two digits of the model number indicate the last two digits of the production/distribution year.