DURNERGY 9V Batteries, 9 Volt Batteries 8 Pack,10-Year Shelf Life, 9V Batteries for Smoke Alarms, Guitar Pedals, Microphone, Smoke Detector Battery, Square Batteries 6LR61 9V Alkaline Batteries

Customers find these 9V batteries to be of good quality and value for money, working well in smoke detectors and musical instruments. The battery life receives mixed feedback - while some say they last as long as expensive name brands, others report them lasting less than two weeks. Power performance and purchase experience also get mixed reviews, with some customers reporting consistent power while others note voltage issues, and some saying they will buy again while others will not purchase again. Additionally, several customers report issues with their smoke alarms beeping.