Save Your Money
I bought 6 of these from a local merchant with the expectation they would outlast a standard 9v Alkaline. Three of them have already failed in less than 2-years. The worst part... ALL 3 of them died in the middle of the night!! Nothing like getting out the ladder at 2am to pull a battery just to get the smoke detector to stop announcing "Low Battery". This past weekend I replaced all 6 with Alkalines. The best part... an 8-pack of name brand 9v on sale cost less than the price of just one of these.