These are amazing blenders and blend with most of my pencils.. the richness it gives is amazing.. except the ones that don't play nice in coloring anyways! I always have them handy! Some coloring books seem to have thicker black lines outlining the designs. One thing I've been impressed with is that it can almost act as an eraser when lighter colored pencils accidentally gets onto the thicker black lines (especially in the chalkboard coloring books) if you take this blender across that black area.. voila the pencil marks are gone! I love the thickness of this blender and it sharpens nicely without ever breaking. This was a great value for your money! It will definitely always be part of my coloring collection.