Chaco was born on the river. The classic Z/Sandal is an icon in the whitewater world—and pretty much everywhere else by now too. As is the classic blue and yellow tie-down strap by Northwest River Supplies (NRS). To celebrate their mutual love of whitewater, and the 50th anniversary of the Wild and Scenic Rivers Act (created by Congress in 1958 to preserve rivers with outstanding natural, cultural, and recreational value) the two have released a custom Z/Sandal.

A staple of river life everywhere, the classic blue NRS tie-down strap is instantly recognizable by all who share a passion for whitewater—plus the thousands of others who’ve found non-water specific uses for them. The Chaco collab sandal riffs on the original design, replacing the usual length designator with “NRS-18” to represent the current year, and 50th anniversary of the legislation.

Just like the NRS straps, these Made in U.S.A. sandals are a no-frills workhorse guaranteed to get the job done and continue doing so for years in the future.

In addition to simply paying homage to the legislation, Chaco is donating $10k to American Rivers—an environmental charity combining advocacy and field work to help protect and preserve key river basins across the country—and its 5,000 Miles of Wild campaign.