It's an A5-ish size with nicely rounded corners and the Cortex brain-y logo is debossed on the front cover. The back cover has a tiny logo and "THEMESYSTEM" at the bottom center. Inside, there's a title page and an intro to the system. The corners of the pages tear away. I didn't like that at first, as it seemed messy, but tearing them off is very satisfying and I've been collecting the wee bits in a box on my desk to use as confetti for next New Year.
The pages include 4 theme pages, 90 daily pages, 12 tracker pages, 13 note pages, and 2 index pages. It's a good breakdown, with enough structure to offer guidance, but not so much that you feel locked into a specific journaling protocol. For example, I still haven't figured out how I'll use the boxes on the journal pages--but I never technically have to figure it out. I can just use them however works best for me that day.