Fuxi
Fuxi 9x12 Spiral Sketchbook
Best for: Students and daily sketchers practicing with pencil and charcoal

Pentalic
A tiny 3 x 4 inch pocket sketchbook with 160 pages of acid-free recycled paper, a water-resistant cover, sewn binding, elastic closure and ribbon.
Best for: Sketchers and travelers who want a pocket book for notes and field work
The Pentalic Pocket Sketchbook is a tiny 3 x 4 inch traveler journal with 160 pages of acid-free recycled paper, sized to carry in a pocket.
The flexible cover is water-resistant and the binding is heavy-duty sewn. Pentalic adds an expandable pocket, an elastic closure and a ribbon marker, and suggests it for sketching, notes and field work.
Based on the manufacturer's Amazon listing.
Small enough for a pocket or bag, so you have paper with you when a scene catches your eye.
160 pages for thumbnails, gesture sketches and field notes.
Pentalic uses alkaline papermaking, which prevents the paper from fading or discoloring, and the sheets are made from recycled stock.
The listing describes a flexible book with a water-resistant cover.
The listing calls the sewn binding heavy-duty and the cover durable.
The band keeps the book shut, the ribbon marks your place, and the expandable pocket holds loose notes or sketches.
Look elsewhere if: you want bigger pages that still travel well. The Moleskine Art Sketchbook (Medium) is 4.5 x 7 inches with ivory pages and a hard cover.
Pentalic Pocket Sketchbook 3 x 4
Choose it for: The smallest everyday carry
Leda Art Supply Pocket Sketchbook
Choose it for: A little more room per page
Moleskine Art Sketch Pad (Pocket)
Choose it for: Thick ivory pages
Fuxi
Best for: Students and daily sketchers practicing with pencil and charcoal
Soucolor
Best for: Kids and students who draw every day or need a pad for art homework
Moleskine
Best for: Sketchers who draw in pen or pencil and want a pad that fits a pocket
MOFUNY
Best for: Mixed media artists and art students who work in several wet and dry media