Brow Pop Nano Ultra-Fine Detailing Pencil. This product is: . An Ultra-Fine Detailing + Feathering Pencil. Why we love it: . Kosas Brow Pop Nano is a long wear, ultra-precise 1 mm pencil for the tiniest hair-like details and a clean, soft natural look. Flick the tiny tip for a feathery, natural-looking effect. The perfect amount of pigment + waxiness means it’s just firm enough for hair-like strokes that stay put. Ideal for the smallest sparse patches, adding realistic details and dimension. Clean, vegan, hypoallergenic.. Kosas Brow Pop Nano is available in 6 shades:. . Taupe (cool blonde)Soft Brown (light brown or dark blonde)Medium Brown (neutral medium brown)Dark Brown (rich dark brown)Brown Black (soft brown black). . Black (true black).