From publisher blurb:
With a wealth of feat options at a player’s disposal, it can be difficult to find something new to define your character. The Equipment Trick feat introduced new ways to specialize around the gear you use the most, differentiating your character from every other rank and-file adventurer.
With Sidebar: Equipment Tricks for Backpacks, you’ll find a dozen exciting new ways to employ this everyday gear in your game, both in and out of combat. You won’t want to leave home without it!