A chain link extractor

A chain link extractor is a device used to separate and join links in a bike chain.

[edit] Usage

[edit] Splitting

Line up the tool with a pin in the chain. Push the pin through the chain, but leave the pin attached the back plate of the chain. This makes it a lot easier to rejoin the chain should you need to.

[edit] Rejoining

Push the pin back through the chain using the same tool. If the link is 'sticky' try pushing the pin slightly too far through the chain, then turn the tool around and push the pin back in flush. Alternatively you can bend the chain sideways back and fore which should loosen the tight/sticky link.