Clothesline hooks are most often used to secure clotheslines and are usually mounted into a pre-drilled hole on a metal post. Installing a nut on either side of the post keeps the line taut and allows for easy adjustments should the line ever need to be tightened. This type of hook can be used for other purposes as well, but it is not meant for any heavy duty applications. Great for holding temporary things like tarps in place as they easily accept grommets.