answer 1
I don't have the #15, but it looks like it would be more for specific crease detail work. The pointed side looks larger than on the #20, so it might be harder to do liner with it. The #20 is great for creating that pop of darker color on the outer 1/4 to 1/3 of the eyelid and blending it up into the crease.
answered 2 years, 8 months ago