Crystal clear overlay enhances custom inserts on front cover back cover and spine Nonstick archival-safe material won't lift ink or toner off of printed pages. One Touch mechanism lets you open close and lock your binder in one easy step Gap Free feature prevents ring misalignment so pages turn smoothly Locking EZD Ring holds up to 50% more than same size round rings (20% more than slant rings) Please Note: The actual binder size is measured by the rings not by the spine