Dual pencil sets / product

Carry over the pencil cut is a very troublesome thing, because it often in our bag draw pencil marks. This pen is designed to solve this problem, the outside layer of cap pulled forward, and fixed in the round of the groove, the cartridge cover on the inside, of course, the use of a short pencil, we can be outside the layer pull back the cover and fixed, thus making the original pencil longer, and use more convenient.