Each Square Scorebook has 60 games. Hand-made with quality materials – thicker cover stock, double Wire-O binding, and water-resistant Rite-in-the-Rain® paper on the inside. Extremely portable, measuring 8.5" x 8.5".
Oddly enough, Sharpie-type pens might be the best for this paper, with one caveat: the same witchcraft that makes the paper water-resistant also keeps ink from absorbing quickly, which can lead to smudging.
Baseball moves slow enough, it likely won't be an issue for most users. Once the ink is dry, it's locked in. But fast writers (and left-handed scorekeepers) may want to think twice on this paper choice.
As always, test your pen(s) on the cover sheet to see what will work the best.