Designed for detailed work, these double-ended art markers feature an advanced dye-based alcohol ink formulation that ensures rich color saturation, impressive laydown, and smooth, silky ink flow. - Prismacolor Premier Dual-Ended Art Marker Set - Cool Grays, Set of 12Sanford Prismacolor Marker, COOL GRY ASRTD 12SET - Includes 108 Cool Gray 10%, 109 Cool Gray 20%, 110 Cool Gray 30%, 111 Cool Gray 40%, 112 Cool Gray 50%, 113 Cool Gray 60%, 114 Cool Gray 70%, 115 Cool Gray 80%, 116 Cool Gray 90%, and three 098 Blacks.