Bút lăn 2 Đen + 1 Màu 3 cây

I’ve been using these refills for a few weeks now and the black ink flows really smoothly from the first stroke, no skipping at all. Swapping in the color one for notes and headings adds just enough variety without feeling gimmicky. The three-pack is a solid value too since I go through rollerball i

The vibrant color refill is a nice change of pace between the two standard blacks, and the ink flows consistently without any skips. I've been using the black ones daily for a week and they haven't dried out or bled through my notebook pages yet.

The two black refills write smoothly and last a while, though the color one is a bit lighter than I expected. Still, for the price, it’s a solid way to mix up my notes without buying a whole new pen.