This model battery is a button shape lithium battery with a nominal 3.6V that is used for small electronic devices. It is a popular Alkaline button cell battery commonly used in cameras, BIOS, CMOS, computer, calculators, toys, and watches.

Specification:
Battery Type:   LIR2025 / 2025
Diameter:    20 mm
Thickness: 2.5 mm

Before the 1st time usage:
This listing is rechargeable lithium battery and the battery shipped with no charge. Due to physical "memory effect", the full charge before the first time usage is required and extremely important to reduce "memory effect" on discharge curve. Incomplete charge before the first usage will significantly impact capacity and life-cycle of battery usage.

Important Note:
The free shipping  item ships by first class mail, in a plain white envelope without tracking number. It may take 5~14 business days for USPS delivery. You will receive a non-trackable reference number from USPS shipping software. This is the way to provide buyer high quality item with low cost.