The famous reusable Wippermann Stainless Steel connector. No tools needed to install or remove! Makes cleaning and drive train maintenance a breeze, and since they work with most chains on the market, you can bring a spare and be assured you can get you or your buddies bike rolling in event of an unfortunate chain-break.
The Connex Link can be used to install or remove your chain without tools. Here's a short video showing how simple, fast, and easy, the Connex Link is: