This is a Passport Size passport sized lined notebook.
Given our days as a student, we believe this is one of the most familiar notebooks people can use. This refill has lines printed in a 6.5mm interval, and uses Designphil’s original paper (called MD Paper). MD Paper pursues the best feeling of writing, and makes ink hard to stain and sink through the other side of the paper. It goes well with fountain pens as well.