So I was a little confused when I read this press release.  I had always thought that you could use lithium batteries in the same place as alkaline assuming the same output and size…?  I’ve been using Energizer Lithiums in most of my gear for years now–should I not have been?

Anyway, Surefire is touting the ability of their new M600 to use both Lithium and Alkaline AA batteries:

The M600 AA’s ability to be powered by two separate types of batteries is a key element to its anticipated success,” said SureFire Product Manager Chris Skahill. “For optimal performance, AA lithiums can be used. But it can also be powered by AA alkalines, which are more readily available and usually easier to find, particularly in remote or rural areas.”

Powered by two lithium AAs, the M600 AA’s solid-state light emitting diode (LED) generates a maximum output of 200 lumens and produces tactical-level output for up to 3.75 hours on a set of batteries. The output and runtime from two AA alkaline batteries is approximately one-third that from lithium AAs, but this reduced output/runtime is theoretically outweighed by the convenience of using these easier-to-find and often less-expensive power cells. But to maximize output and runtime, SureFire recommends powering the M600 AA with lithium batteries whenever possible.

I know that lithiums have a more consistent output over their life and can operate in a wider temp range, but I’m not entire sure why they are promoting this as a having power source versatility since it is the same size of battery.  The other SureFire Scouts use the 123A batteries–so I could see a model that can use either AA or 123A as having versatility.  Am I missing something here?

Specs:

Max Output–White Light: 200 lumens
Tactical Runtime: 3.75 hours
Length: 6.875 inches
Bezel Diameter: 1.125 inches
Weight: 5.2 ounces
Batteries: 2 AA lithium (incl.) or alk.
MSRP: $299

Link to the new model:
http://www.surefire.com/m600aa-dss-scout-light.html