What is CMOS battery
This battery allows the BIOS to maintain settings on the computer. These settings include recognizing hard drive settings�� USB on-board device settings and keeping your system clock on time. Usually�� the first visible sign that you need to replace the CMOS battery is that your laptop clock keeps losing time. A CMOS battery can last from three to five years.


Compatible with:

Compaq Presario Series

F500, F502, F503, F505, F506, F551, F552, F553, F555, F557, F558, F562, F564, F565, F577 

P/N: 431436-001



Package : One pcs of Real Time Clock (RTC) CMOS Battery .