It is compatible with pencils measuring 4–10 mm in diameter

It's also refillable and you can change the tip

flexible brush tip that lets you easily switch between thin and thick lines in a single stroke

The Moleskine A3 Sketchbook Hard Cover Plain measures 297 x 420 mm

and water resistant

moleskine a4 sketchbook hard cover plain hidden-product It is compatible with pencilsThe Moleskine A4 Sketchbook Hard Cover Plain measures 210 x 297 mm, a convenient size for sketches and notes on the go. It features 165 g m ivory colored paper thats acid free, keeping your drawings safe and clean. The hard cover protects your work, and it opens flat at 180, making it easy to draw across both pages. Rounded corners, an elastic closure, and a matching bookmark ribbon make it practical to use, while an expandable pocket at the back and