Let me tell you why these little powerhouses have earned a permanent spot in my emergency drawer. When my home security system started beeping with a low battery warning at 2AM, I grabbed one of these Duracell CR123As - and it's been silently protecting my house for 14 months straight without a single hiccup.

The real test came during last winter's blackout. My 'emergency flashlight' that I hadn't touched in three years? Powered by these same batteries. Flicked it on expecting dim light, but got full brightness instantly. That's when I understood the '10-year storage' claim isn't just marketing - these things are like energy vampires that refuse to die.

What surprised me most is how they outperform in extreme conditions. My trail cameras running on generic batteries would freeze up below 20°F, but the Duracells kept capturing crisp wildlife shots through an entire Vermont winter. The slightly odd size (bigger than AA but smaller than C) actually became an advantage - no more fumbling in the dark trying to insert batteries the wrong way.

Yes, they cost more upfront. But when my neighbor was on his third set of budget batteries for his smoke detectors while my initial Duracells were still going strong, the math became obvious. For critical devices where reliability matters more than saving $2, these are absolutely worth it.