When you learn hard pen, you need to know the relevant knowledge of ball pen factory with hard pen tools. Ball point pen is one of them, sharing the knowledge about ball point pen's structure classification.
A disposable pen, pen refill is, neither gas nor change ink cartridge, ink runs out, can only be discarded.
It can change the ball pens, ballpoint pen factory function button, spring, lock, restoration ballpoint pen manufacturers.
The pen holder can be rotated to extend or retract into the cartridge.
We have combined the ballpoint pen, a ball pen and pencil combination, ballpoint pen and the test pencil combination, a new pen pen and small bulb combination etc..