GM's Aid IX: Universal Monster Rules
The Universal Monster Rules and Simple Templates of the Pathfinder Roleplaying Game allow for quick identification of a creatures capabilities or quick modification of a creature to make it a bit stronger, weaker or just different. But in order to use either, the GM must constantly flip back and forth between pages in the Pathfinder Roleplaying Game Bestiary, from the creature itself to either the universal rules or the simple templates. If doing this on the fly in the middle of a game, this can drag the game to crawl very quickly.
Now, with GM's Aid IX: Universal Monster Rules and Simple Template Cards, the GM can always have both handy for quick reference. Simply print the sheets out, cut them into quarters, and you instantly have a neat stack of simple cards to look through when adjusting a creature's stats or when looking for the specific information about a Trample attack or the Blindsight ability.
As a GM, you'll be happier about not having to flip back and forth in your book all the time, and your players will be happy that your game continues to run at a good pace and no longer bogs down while you look something up.