The first thing you’ll notice about Vivo’s Barefoot Ultra running shoes is the perforated upper. It’s made of molded ethylene vinyl acetate (EVA), a soft and flexible material that’s resistant to both the abuses of running and potential damage from the elements.

But the shoes really stand out thanks to their resemblance to one of the last decade’s greatest eyesores: Crocs. Unlike Crocs, however, these can be worn in public without embarrassment or shame.

The Vivo Barefoot Ultras are true minimalist running shoes. They aim to give you an experience that’s as close as possible to running in bare feet. There are other shoes feeding this craze, like Vibram’s famous FiveFingers toe-shoes and Merrell’s Barefoot runners. As any fan of barefoot running knows, some of the design choices made by these shoe manufacturers are dubious, as they apply radical technologies and materials in their attempt to lighten the load or arrive at their minimalist goals.

But Vivo’s Croc-like vibe has a great advantage — the hexagonal, honeycomb-shaped perforations allow the shoe to drain instantly in wet conditions, making them practically amphibious.

The sole has the same honeycomb design, but in the form of nubs that provide traction. Keeping with the theme, the interior liner snaps into the heel with a honeycomb-shaped tab.

The shoes can be worn three ways: The upper and plug-in tongue can be worn with socks like a traditional running shoe, the removable liner can be used in place of socks for a “barefoot” run, or the cage-like upper can be worn on its own.

The last scenario is most useful on the beach — when I competed in the Big Kahuna triathlon in Santa Cruz, California, I debated leaving the uppers at the swim finish so I could use them to run to the transition area a quarter of a mile away.

No matter which configuration you choose, they’re astonishingly light. With the upper and liner assembled, the shoe weighs only four and a half ounces (the uppers alone weigh about three ounces) in a women’s size 8.5.

The 6mm sole provides zero drop, meaning you’ll experience that heavy feeling of landing flat-footed while you’re adjusting from regular running shoes or a transitional pair. The sock liner — a combination of nylon, airprene and neoprene — is about 2mm thick. Combined with the EVA cage, this provides a more comfortable sole than other minimal shoes, where every pebble is felt in a The Princess and the Pea sort of way. The Vivos have what could be described as a slightly springy feel, which I happened to like, but I realize the purists of the barefoot running community may not appreciate it.

I have narrow feet, and the upper has a rather wide cut, so adding the liners gave a nice, snug feeling to the fit. But the liner also caused my feet to get unpleasantly hot while running. One of the big reasons they typically make wetsuits out of neoprene is because it retains body heat in cold salt water. As to whether you’d prefer the extra insulation or not, that’s a matter of individual preference. And luckily, the shoe is configurable enough that you can swap out the liner for something better suited to your running conditions. But if you like the liners, you may want to stock up on your anti-fungal cream.

Both the men’s and women’s versions of the Vivo Barefoot Ultras come in five different color choices. Alas, mine are white, so they have been retired until next Memorial Day.

WIRED Amphibious, lightweight and comfortable. Vegan. Configurable design matches multiple running styles. 6mm-thick, zero-drop sole gives a barefoot feel with a slight spring to each step. Great for the beach. Adjustable locking cord system replaces traditional laces (for the better). The company says its polymer-heavy shoes are produced sustainably and ethically, from locally sourced materials.

TIRED Liners trap heat in and don’t breathe well. Like other barely-there shoes, sizing is fickle. They look like Crocs — there’s no nice way to say this.

Photo by Sara Peschel/Wired