The HP RR03048XL-PR is a primary lithium-ion replacement battery for compatible HP laptops. It is also identified as HP part number 851610-855, which can help match it to the listed systems.
Its four-cell design has a charge capacity of 4.21 Ah (4210 mAh) and an energy capacity of 48 Wh. These figures describe its cell count and stored energy.
Compatibility is listed for HP Mobile Thin Client mt20 and mt21, plus HP ProBook 430 G4, 440 G4, and 450 G4. Check the model against this list when choosing a replacement power source.