Quick links are commonly used as rappel hardware, but they can loosen over time and of course work better when the sleeve is locked down tight. If you find a loose quick link on a route, here's how you might be able to tighten it, provided you have another link with you. This lets you apply a lot more torque then you can with just your fingers.

Notes:

• This method is meant for field improv. Obviously, the best tool for this job is a crescent wrench or pliers.

• It's best practice to install quick links so the sleeve threads down to close, not upwards. That way it's more likely to stay closed.

• Quick links are a rather heavy, single use piece of gear, and many people will choose not to carry them. For some routes it makes make sense to have them, for others perhaps not.

• It's best practice to use proper CE rated quick links for climbing rather than random ones from the hardware store. CAMP makes inexpensive, super-strong quick CE rated links in three different sizes, read more about those here.

Like many things in climbing, it's a better show than a tell. Here's a quick video I made to show how it works.