HP and Compaq are the same company.

HP e Compaq sono la stessa azienda.

The part number is essential when shopping for a new laptop battery. Part numbers are unique identifiers assigned to parts, making them easier to reference and clearly defining parts within a single manufacturer. Knowing your battery's part number makes purchasing the right battery faster, and looking up a battery by its part number is more accurate than looking it up by its laptop model name.

HP is one of the easiest brands to find battery part numbers. There should be a white sticker with a barcode on every battery, and on this sticker, there is what HP calls a “Spare” number. Usually the sticker shows, “Replace with HP spare” and following that are 6 digits with a dash and 3 more digits. There are various other numbers stamped on HP batteries that you can use to cross reference if the white sticker is damaged or missing. These numbers start with “HSTNN” and then a dash and several numbers and/or letters. On certain batteries, there is also a number/letter code near the HP logo. This code is two letters followed by a few numbers.