The Energizer 389/390 is a 1.55V silver oxide button cell for watches, calculators, glucose monitors, and other low-drain electronics. Silver oxide chemistry holds a flat voltage curve through most of the cell's useful life, so devices that depend on a stable supply (digital readouts, timekeeping circuits) keep working accurately right up to end of life - unlike alkaline button cells which sag in voltage as they discharge.

• Chemistry: Silver Oxide (Zn/Ag2O)
• Voltage: 1.55V nominal
• Capacity: 73 mAh (high-capacity cell in the silver oxide button family)
• Dimensions: 11.6mm diameter x 3.1mm height
• Zero mercury formula
• 5-year shelf life

Replaces: SR1130W, SR1130SW, SR54, 189, AG10, LR54, LR1130, V389, V390, and other 389/390-equivalent batteries.

Common uses: watches (especially analog watches with extended runtime expectations), calculators, glucose monitors, digital thermometers, keyless entry systems, and laser pointers.

Tip: Install with the positive (+) flat side facing up unless your device documentation says otherwise, and handle the cell by its edges - skin oils on the terminal can shorten shelf life. Store unused cells in their original card at room temperature, away from coins or keys that could short the terminals.