The HP M45131-001 is a laptop CPU cooling fan listed for selected HP Pavilion x360 models. It is a replacement part intended to move air through the laptop’s cooling system and help cool the processor during use.
The fan has a 4-pin connection. The retailer lists it as suitable for HP Pavilion x360 15-er0000 and 15-er1000 models, providing a specific compatibility reference for this part number.
This listing identifies the fan as an HP part and gives M45131-001 as its exact item number. It is described as a fan without a heatsink.