Stalogy Notebook
We love these notebooks for journaling, bullet journals, and many other uses. You can get in different sizes that work for your planner. The cover is thin and flexible and more lightweight than a Hobonichi if you are adding to a planner. The A6 and B6 sizes are the most popular. We enjoy using this in a Moterm B6 Planner Cover or a Gillio Appunto in A6 or B6. What I love is that the pages are plain grid and you can use this however you want. I find it excellent for journaling. The pages are slightly brighter than Hobonichi.