4mm, 5mm, 6mm, 8mm, 10mm, and 12mm.
The different lengths provide flexibility depending on the setup and type of application being used. For reference, 8mm and 12mm are considered standard syringe tip sizes, while shorter tips such as 4mm, 5mm, and 6mm may require slightly longer engagement to ensure complete fluid transfer. All pens are designed to work with a standard 3mL cartridge and universal pen needles, operating in single unit doses up to 60.