This product is very similar to the Stila Stay All Day Brow Tint Pen except you wear it overnight.  I used this at night to fill in my brows.  The next morning, my eyebrows were still there, even after I washed my face, but the tails of my eyebrow were a little faded.  I still touch up my brows with the brow powder in the morning to make it look more natural. My brows stayed on the whole day, but after I wash my face at night, the color on my eyebrow is lighter and the product on the tips of my eyebrow is almost gone.  I wish this product had a soft brush pen tip instead of a thick marker tip because it's hard to draw on hairs.  You have to be careful not to use too much or it will look like you drew on your eyebrows with a marker.  The staying power is great on eyebrow hairs.  But for parts of eyebrows that doesn't have that much hair, you may have to touch up more often.  I wish they had a taupe-brown color because the dark brown is slightly too warm for me.