Each book contains: • 2”x4” with die cut rounded corners • 100 sheets of 100lb/160gsm European acid-free bright, natural white paper • slightly toothy paper but not enough to catch even the sharpest dip nib • sturdy chipboard covers letterpress printed with a crisp application of "afterburner" black • handy split ring so pages can be removed, rearranged and reinserted as needed Paper was rigorously tested to ensure that inks would not feather, bleed or show through. Inks can be tested with fountain pen, glass pen, dip pen, swabs or paintbrush on the front or back of the sheet . Col-o-ring Ink testing books are printed, assembled and designed in Kansas City. Paper was sourced from a local distributor. (For orders of 100 or more, please message us)