FBWC battery on DL360 Gen9 Base Model

We plan to buy DL360 Gen9 Base Model (755262-B21) with preinstalled P440ar/2Gb.

We need Write Caching to be available on server.

Surfing datasheets it is not clear is this server has FBWC battery installed? Or should we buy it as an option 727258-B21 ?

As I can see when buing P440ar as an separate option kit (726736-B21) we'll get the battery as well:

NOTE: HP Smart Array P440ar/2GB FBWC controller option kitincludes the HP Smart Storage Battery the backup power source necessary to protect the data on the  Flash-backed Write Cache as the P440ar will generally be your default P-series controller and will require the HP Smart Storage Battery and therefore included.

But what about preinstalled P440ar?

Thanks,

Andrey