Index that does not protrude from the cover. Features: This is an index sticker that does not protrude from the cover. Designed to pop out 0.1 inch (2.5 mm) to fit into a standard notebook cover. The removable sticker makes it easy to reposition and move. ·Do not use water based pens when writing, use a pencil, a permanent ballpoint pen or a permanent sign. Ink and toner may adhere to the adhesive surface. Please try before use. It may not be used on rough surfaces or surfaces with moisture, oil, and dust. Avoid storing in direct sunlight, high temperatures and humidity.