On Mar 29, 8:38 pm, Mike Adams wrote:


I have the ACK unit with the D cell batteries. It requires the duracell batteries with a date code, not just
the ordinary flashlight batteries. They are good for 4 years.


The last batch of Duracell D cells I bought were good for 7 years from
the time I purchased. According to this ACK manual
http://www.ackavionics.com/images/Mo...ELT_Manual.pdf, you only
need to replace the batteries before the expiration date.

Of course, it's probably a good idea to replace them before that,
particularly the fact that you can reuse those D batteries in
flashlights.