Okay, so I grabbed these Voniko 9V batteries after reading some mixed reviews, and honestly? They’re a steal. Super affordable, and they actually work. I’ve been using them in my smoke detectors (tested monthly, no issues).

The packaging is simple but eco-friendly—no mercury or cadmium, which is a nice touch. Plus, they claim a 7-year shelf life? I haven’t tested that yet, but if true, that’s impressive for the price.

Compatibility is solid too. Fits perfectly in my smoke alarms (no awkward sizing like some off-brands), and the voltage reads strong out of the box (9.69V on my meter). No chirping or weak signals so far.

Durability is the real test though. I’ve had one in use for about 9 months, and it’s still going. If these last a full year, the savings over name brands will be insane—imagine cutting battery costs by 50-70% long-term.

Leakproof design is a bonus. No mess, no stress. For the price, these are a no-brainer if you’re stocking up for smoke detectors or low-drain gadgets. Will definitely repurchase!