A study published this month by researchers at Duke University suggested that neck gaiters, the kind made of polyester spandex material, did a terrible job of blocking viral particles and were not recommended as face coverings to ward off the coronavirus.

However, neck gaiter manufacturers defended their gear saying “all gaiters are not created equal,” according to The Washington Post. “There’s a segment of this category that’s of a much higher quality that’s engineered to be layered," said Chris Bernat, co-founder of South Carolina-based Vapor Apparel.

New research bears this out. According to The New York Times, Dr. Linsey Marr, one of the world’s leading experts on aerosol transmission, put gaiters to the test along with Jin Pan, a colleague at Virginia Polytechnic Institute and State University. They tested single layer and double layer gaiters made of polyester and spandex, respectively.

Both types of gaiter prevented 100% of large 20-micron respiratory droplets from filtering through, but the single layer polyester face covering blocked only 10% of the tiny, 0.5-micron particles, while the double layer blocked 20%.

However, when the scientists doubled the single-layered mask, it prevented 90% of the smaller particles, exhibiting more than twice the efficacy of the cotton masks recommended by the Centers for Disease Control and Prevention, according to the Times.

“I’ve been recommending neck gaiters, and my kids wear neck gaiters,” said Marr. “There’s nothing inherent about a neck gaiter that should make it any worse than a cloth mask. It comes down to the fabric and how well it fits.”