Mallory No. RM-401H Mercury Hearing Aid Battery
The Mallory No. RM-401H 1.4 volt mercury hearing aid battery was made
by the Mallory Battery Company of Canada Limited probably between 1955
and 1965 or
so.
The No. RM-401H mercury battery weighed 0.3 oz. (8 g) and measured 1⅛"
by 7/16" in diameter
(2.9 x 1.1 cm).
Note: the first series of pictures shows the Canadian version of the
Mallory RM-401H, while the second series of pictures shows the British
version of this same model of battery.
|
 |
Click picture for larger view |
| |
 
|
|
|
|
Bottom view of the Mallory No. RM-401H mercury battery showing patent
number 2542575.
|
 |
Click picture for larger view |
| |
|
|
Front view of the Mallory No. RM-401H mercury battery showing the model
number and voltage (bottom). This battery, a size "N" (also
referred to as size 401), was a
popular size of battery for hearing aids used from the mid 1950s and
still in use today.
|
 |
Click picture for larger view |
| |
|
|
Side view of the Mallory No. RM-401H mercury battery showing where it
was made. It also shows 3 more Canadian patent numbers—452347, 486024
and 499194.
|
 |
Click picture for larger view |
| |
|
|
Another side view of the Mallory RM-401H mercury battery showing the
polarity. Interestingly enough, the positive terminal is on the bottom.
|
 |
Click picture for larger view |
| |
|
|
Top view of the Mallory RM-401H mercury battery showing the
negative terminal.
|
 |
Click picture for larger view |
| |
|
|
Bottom view of the Mallory RM-401H mercury battery showing the
positive terminal.
|
 |
Click picture for larger view |
| |
|
|
This is the British version of the Mallory RM-401H mercury battery.
The battery itself is exactly the same size, shape, etc. It is just the
paper label that is different. This may be an earlier version of the
above battery with a different (British) design.
|
 |
Click picture for larger view |
| |
|
|
Front view of the British version of the Mallory RM-401H mercury battery.
It reads, "Mallory, Mercury battery for hearing aids, RM-401H".
|
 |
Click picture for larger view |
| |
|
|
Back view of the British version of the Mallory RM-401H mercury battery.
It reads, "Mallory Batteries Ltd., Made in England, U.S. Pat 753090 Et
al., Warning: battery ... (the rest is unclear).
|
 |
Click picture for larger view |
| |
|
|
Left side view of the British version of the Mallory RM-401H mercury battery showing the
positive terminal to the right (bottom of battery).
|
 |
Click picture for larger view |
| |
|
|
Close-up view of the British version of the Mallory RM-401H mercury
battery showing the model number (RM-401H).
|
 |
Click picture for larger view |
| |
|
|
Top view of the British version of the Mallory RM-401H mercury battery showing the
negative terminal.
|
 |
Click picture for larger view |
| |
|
|
Bottom view of the British version of the Mallory RM-401H mercury battery showing the
positive terminal. The inscription reads, "Pat. No. 753090 Et. Al."
|
 |
Click picture for larger view |
| |
|
(If a larger picture doesn't appear, you may have to
turn your pop-up blocker off)
|
|
|
