office supplies european standard gel pen plastic student signature pen black 0.5mm bullet brush-through pen wholesale 办公用品欧标中性笔塑料学生用签字笔黑色0.5mm子弹头刷题笔批发

black [bullet] blue [bullet] red [bullet] black [syringe head] blue [syringe tip] red [syringe head] bullet refill, black refill syringe with a black head

0.5mm