Hot sales friction pen, stick function erasable gel pen with cap and eraser, school and office use, ergonomic soft grip shape design, writing smooth, 0.6/0.7mm tip, Promoting a custom heat-sensitive ergonomic gel pen that is refillable and erasable, with a beautiful writing quality. The pen likely uses friction-based ink, which can be erased using the heat generated by rubbing the eraser on the pen's end over the ink. This pen is designed to be both comfortable and functional for use in both school and office settings. Its heat-sensitive feature may be useful for tasks that require temporary writing, such as taking notes or making corrections on documents. Overall, this pen seems to have several features that make it a desirable writing tool for those looking for a comfortable and practical option.