CP1W-BAT01 is a battery unit designed for Omron PLCs. It is used to provide backup power to the PLC's internal memory in case of a power failure. The battery unit ensures that the PLC retains its program and data even when the main power supply is disconnected. The CP1W-BAT01 is compatible with various Omron PLC models, including CP1E, CP1H, CP1L, and CJ1 series. It is a replaceable battery unit that can be easily installed and replaced when needed. The battery has a long lifespan and provides reliable backup power for the PLC system.