In Japan, black and gray ink pens are used frequently during the holidays for elegant writing on cards in announcements. Many American artists and crafters have fallen in love with such pens because it combines often used colors for artwork. The pen is double-sided with a black ink felt tip marker on one side and a gray ink marker on the other side.
however, a second reason that this Marker is so popular is because of its balanced and light weight that makes it perfect for pen spinners. It is the pen for the popular Dr. KT mod.
For more information about pen spinning check out this video:
This pen (I would place in Brush pen category) is similar to Zebra brush pens
with (similar) tip that creates variation line according to how hard you press.
Advantage is you have both black and grey tips. For drawing or for writing large
Both sides write cleanly with great color. It feels good in my hand and is
perfect when you don't want to carry a large pen case. Personally I like a very
fine point for note taking (0.35 at most) but this would be a great writing pen
for many people.
I use it for drawing and designs. For a minimal drawing kit i take this pen, a
mechanical pencil with good eraser and a small sketch book. I make puppets and
swear by two color design drawings. One color for the look of the puppet and
another for the controls.