Patented three-chamber EnduraGlide dry-erase marker always delivers strong, bold color. Non-toxic, low-odor ink is safe and easy to use. See-through ink gauge shows exactly how much ink is left. Communicate boldly with quick-drying, vividly colored ink. Ideal for use on whiteboards and nonporous surfaces. Sends ink straight to nib from three separate pressurized chambers, ensuring constant ink flow, smoother writing and clean erasure. Convenient see-through barrel shows exactly how much ink is left. Roll-resistant cap prevents markers from drifting out of sight.