The Brush Tip allows you to draw both fine and broadlines with a bolder and smoother doodling experience. The Pen is perfect for creating dimension in lettering, and cartoon detailing and is great for designing on your PYO (Paint Your Own) cookies. The best part about the Brush Pen is fast drying, smudge-proof and bleed proof! The Brush Tip is great for filling in fonts and wider designs (allow 30 sec dry time)The tweets Pens are smudge and bleed proof and will resist any extract, vodka or Everclear when mixing with gel food colors, Luster, Petal, Matte and Metalic dust powders. Painting with water is not recomended. Pens are designed to be used on dry Royal Icing, Dry Fondant, Wafer Paper, FlexFrost Fabric, and Gumpaste. The Brush tip is also great to use for outlining on naked cookie surfaces.