H1K90a5 is an extended warranty and proactive service agreement. It is not an HP part number or model number for a battery. If you are trying to find a replacement battery for your HP laptop or tablet, go to our HP battery page. Or you can search our site for your battery part number or model. You can find what HP model number you have by looking near the laptop screen and keyboard. You can find your battery part number by removing the original battery and looking for the HP spare part number listed on the bottom of the battery. Make sure you power off your computer before removing the battery. Some batteries are snap-in and some are internally located and require a small screwdriver. Here you can read our article on how to find your HP battery part number.