1957 Hitachi TH-621 (1959 example)
Shirt pocket radio, thermoplastic cabinet
4 1/2 x 2 7/8 x 1 5/16 inches / 114 x 73 x 33 mm
Six transistors (Hitachi, 2N215, 2x 2N217, 2x 2N218, 2N219, + 1N34A glass diode)
One 9-volt battery
Manufactured by Hitachi Ltd., Tokyo
(Chassis manufactured by Standard Radio Co. for Hitachi)
One of a very few Japanese shirt pocket transistor radios made in 1957 — and as Alan Kastner has pointed out on his TH-621 pages, the chassis for the Hatachi TH-621 actually was made by Standard and is identical to the chassis of the Standard SR-F22.
And as with most transistor radios from any country, the TH-621 was produced for more than one year — in this case, at least up through early 1959: the TH-621 example shown here has electrolytics dated to February 1959. Also, see the July 1959 internal price sheet below from a "Top-Line" radio distributor.
According to the Hitachi brochure page shown below, the TH-621 came in six(!) different cabinet colors — I've seen all but the blue one and the pink one. So, if there were a blue one and a pink one (no guarantee that there actually were), then make that seven colors when you include the black Hitachi TH-621 that came out under the name and model number of the AMC TR-600 — and it still seems a bit odd to me that Hitachi apparently didn't make a black TH-621 under its own name.