Create Your Own Socket Key Pocket Keychain
Keychains are a great toolbox , but one tool that always seems to be missing is the socket wrench. On Instructables, DIYer M3G fixed this with a pocket socket wrench.
M3G uses an old socket wrench and steel tube to make its tool, but you can probably retrofit with another pocket tool (a set of folding hex wrenches seems perfect for this) if you don’t want to weld your own. Then he simply selects a few of the most commonly used outlets, attaches them to the keychain, and carries them with him all the time.
Pocket Socket Wrench (Keychain) | Instructables