Park’s Mini Chain Brute Chain Tool goes anywhere and features a V-shaped handle, a super-strong replaceable pin, and fine threads to make chain removal and installation a breeze. The CT-5 works on any derailleur chain, including Shimano Hyperglide and 9-, 10-, and 11-speed. It works for loosening tight links, too.
WARNING for residents of California:
WARNING: Cancer and Reproductive Harm