Rayovac R-401 and RP401 Mercury Hearing Aid Batteries
This is an Rayovac RP401 1.4 volt heavy duty mercury hearing aid battery used as the "A"
battery in the
vacuum tube hearing aids and as the only battery in transistor hearing aids in the 1950s.
This battery weighs just over ˝ oz., and measures 1 1/8" by
slightly under ˝" in
diameter. Mercury batteries of this size were known as "N" batteries.
Mercury batteries
are no longer sold today because of the large quantities of mercury in
them, and the consequent environmental concerns.
This battery was equivalent to the Beltone BP401R, the
Duracell RM-401H, the
Eveready E401E
and the Zenith ZM401.
|
 |
Click picture for larger view |
| |
 
|
| |
|
|
An earlier version of this battery was called the Rayovac R-401.
|
 |
Click picture for larger view |
| |
|
|
Side view of the Rayovac RP401 mercury battery showing the model number
and voltage.
|
 |
Click picture for larger view |
| |
|
|
End view of the positive terminal of the Rayovac RP401 mercury battery.
|
 |
Click picture for larger view |
| |
|
|
The Rayovac RP401 mercury batteries came 2 to a box.
|
 |
Click picture for larger view |
| |
|
|
End view of the Rayovac RP401 box showing the cutout at one end.
There was a similar cutout on the other end. This made it easy to test
the voltage of the batteries without taking them out of the box. That
way a customer could be sure he was getting "fresh" batteries.
|
 |
Click picture for larger view |
| |
|
(If a larger picture doesn't appear, you may have to
turn your pop-up blocker off)
|
|
|
