From the product description:
An ultralight old school roleplaying game in Pocketmod format, with rules to convert from other OSR games. Create an Adventurer, Cleric, Fighter, Magician, Dwarf, Elf or Halfling and run adventures with magic, challenges, and deadly encounters. This is the smallest old school gamebook on the market, and you can print, fold, and take it with you within minutes.
Adapted from the popular Weird West RPG, this pocket-sized fantasy RPG been designed to make reading, creating characters, and starting a game as fast as possible. We've cut out the 'what is an rpg', game fiction, and other 'fluff' to keep the rulebook as lean while still having enough detail to make it fun. When you want to add more detail to a game of Strange Magic, or adapt a published adventure, we’ve included rules to quickly convert between popular ‘OSR’ rules. Being OSR compatible means you can also adapt any of the rules in Strange Magic to your favorite game as well.
This purchase includes both a PDF version suitable for reading on your computer, iPad or iPhone and a special 'PocketMod' PDF version for printing. The PocketMod version lets you create your own 4.25" x 2.75" sized game books from a single sheet of paper. Take a copy to read on the go, and print one to give to each of your players.