Ink is formulated to erase easily and cleanly. Improved color vibrancy and long-lasting writing. Marks on whiteboard, glass, and other nonporous surfaces. Durable chisel tip marks in a variety of widths. Cap can be left off for 24 hours without dry-out. Safe to use at home or school. Low odor, non-toxic. Desk-Style Value Pack—24 for the price of 20! Marker Ink Type: Dry Erase; Marker Tip Type: Chisel; Marker Tip Size (text): Broad; Marker Tip Size (numeric): 4.8 mm.