Unique Design: Ultima A6s needle cartridges are unique and elegant in design to enhance the look of your pen. Cartridges: Replacement cartridges. You can replace them easily. Easy to Use: These needle cartridges are readily useable, just place them on the pen and enjoy the benefits of micro-needling. Adjustable: You can adjust the length of needle cartridges (length of needles is 0.25mm to 3.0mm) according to your requirement. Users' Safety: These cartridges are individually sealed to ensure the hygiene of the users and packed in a way that will not cause any discomfort to the carrier. It provides Premium quality and elegant design Micro-needling Cartridges for Ultima A6s. These all are individually sealed cartridges for better hygiene and sterilization, keeping in mind the safety of users. The adjustable knob feature enables you to adjust the length of cartridges according to your requirement.