Energizer 395/399 Silver Oxide Button Cell Batteries (10 Pack)

The Energizer 395/399 is a 1.55V silver oxide button cell battery sold in a 10-pack, compatible with watches, calculators, hearing aids, glucose meters and other precision electronics requiring stable voltage. The 395 and 399 designations are interchangeable references to the same battery size, sometimes also listed as SR927SW or SR57. Silver oxide chemistry delivers more consistent voltage across the discharge cycle than alkaline equivalents, making it the preferred choice for devices where timing accuracy or precise readings matter.

Each cell measures approximately 9.5mm diameter by 2.7mm height and weighs around 1g, fitting the same battery compartment as LR927, AG7 or SR927W alkaline cells but offering better performance in high-drain applications. The 10-pack format suits users maintaining multiple watches, replacing seasonal device batteries (such as glucometers or remote controls), or stocking spares for professional repair and service environments.

Energizer builds these cells with leak-resistant seals to protect device internals from corrosion during use and storage. The silver oxide composition holds voltage near 1.55V for most of its lifespan before dropping sharply at end-of-life, giving clearer replacement signals than the gradual fade seen in alkaline cells. Shelf life typically extends 3-5 years when stored at room temperature in the original blister packaging.

What devices use 395/399 batteries?

Common applications include analogue and digital watches, small calculators, hearing aids, glucose meters, laser pointers, keyless entry fobs and some camera light meters. The 395/399 size is one of the most widely used button cells for precision devices.

Can I use alkaline LR927 or AG7 instead?

They fit the same compartment, but silver oxide 395/399 cells maintain more stable voltage and last longer in devices sensitive to voltage drop, such as quartz watches. Alkaline equivalents work but may cause timekeeping drift or early low-battery warnings in some devices.

How long do these batteries last?

Runtime depends on the device. In a typical analogue watch drawing 1-3 microamps, a 395/399 silver oxide cell lasts 2-3 years. Higher-drain devices like calculators with frequent use or hearing aids will see shorter life, typically 6-18 months.

What is the shelf life?

Energizer silver oxide cells hold charge for 3-5 years when stored in their original blister packaging at room temperature. Store away from direct heat and humidity to maximise shelf life.