2. Remove the pen cover, unscrew the pen cover and prepare the refill kit bag, as shown in the figure below.
3. Align the western end of the ink bag with the bayonet and press it hard until you hear a click, and the installation is complete.
4. After the installation is completed, you can write normally by hanging the pen upside down for one minute, as shown below.
Don't poke the ink sac with other sharp objects before putting it into the pen, which will do great harm to the pen.