Amps
The style of serial numbers on white plastic plates riveted onto the rear face of the chassis, as introduced for the TV10 and TV15 combos in 1952, was continued on the four combo amplifiers made throughout Selmer's Maroon/Grey period. The model numbers preceded the serial number on the plates.

Serial # 18/457 - White Plastic Plate on a Selmer Truvoice TV18 Combo.

Serial # 20/232 - White Plastic Plate on a Selmer Truvoice TV20 Combo.
| Model | Serial # | Location of Serial # |
| TV6 | 6/160 | White Plastic Plate |
| TV6 | 6/1308 | White Plastic Plate |
| TV6 | 6/2457 | White Plastic Plate |
| TV12 | 12/742 | White Plastic Plate |
| TV18 | 18/199 | White Plastic Plate |
| TV18 | 18/261 | |
| TV18 | 18/457 | White Plastic Plate |
| TV20 | 20/232 | White Plastic Plate |