HP Digital Pen 250 User Manual page 15

Pull the cap away from the pen. The ink cartridge should pull away with the cap. Remove it
4.
completely from the pen and discard it.
Insert a new ink cartridge into the pen.
5.
Press the pen tip against the surface of a notepad to secure it in place.
6.
You can get additional refills at local office supply retailers. Make sure that refills you buy are compliant
with the ISO 12757-1 standard.
Caution: Make sure the refills do not contain carbon because carbon ink can interfere the pattern on
the paper, causing errors.
HP Digital Pen 250
Chapter 2 Getting Started
User's Guide 15