Westinghuse Dynamo Alkaline 9V Batteries are a handy choice for everyday use in a wide variety of devices around your home or office. These Westinghouse Dynamo Alkaline Batteries do not contain mercury. This is a Westinghouse Dynamo 9V Battery 1-pack. Users can expect long-lasting performance from these batteries in a wide array of devices. Users can expect these batteries, when unused, to remain fresh for up to ten years.