Stealth Wear, Coming to a Store Near You

A promotional video from Adam Harvey and Johanna Bloomfield for the OFF Pocket sheath.

Stealth wear, clothing and accessories created to protect their wearers from surveillance, has largely been an abstract concept. Most designs are created as prototypes, not items that can be purchased in a department or drug store.

But Adam Harvey, one of the designers interested in developing countersurveillance fashion, is working to bring some of his ideas, which include anti-drone detection hoodies, to the mainstream.

He recently created a project on Kickstarter, a crowdfunding site, to see if he could drum up enough interest to finance a cellphone accessory, the OFF Pocket, which looks like a small sheath for a mobile device. It works as an electromagnetic barrier, functioning as something known as a Faraday cage, a space where radio waves cannot pass through, preventing the penetration of signals that transmit data and audio. It replicates the refrigerator trick that Edward J. Snowden used to keep his cellphone from transmitting information about where he was staying.

Mr. Harvey and his design partner, Johanna Bloomfield, originally set out with the modest goal of raising $35,000, enough to manufacture a small line of their phone protectors. But the project hit its goal in seven days; it currently has close to $60,000 pledged through the site. Nearly 600 OFF Pockets have been ordered, he said.

Mr. Harvey attributes the swell of interest in the project to the rising awareness of privacy and security concerns.

“People are more aware about what kind of tracking is going on and much more interested in ways to learn about privacy,” he said.

Mr. Harvey said he had been working on the concept for the OFF Pocket since 2011. The first version  was designed as a permanent pocket in a pair of his jeans. The smartphone sleeves currently cost $85 each, but Mr. Harvey hopes to begin manufacturing enough of them to bring the cost down.

Mr. Harvey said that he could not afford to hire an outside firm to extensively test the effectiveness of his products, but that he tested them himself with most of the popular smartphones and major wireless carriers.

The design, which weaves together a number of different metal and nylon materials, “works like a metal cage but is entirely flexible and made of fabric,” he said.

“Everything bounces off,” he said. “Inside, there’s zero signal.”

Mr. Harvey is also working on a collaboration with the New Museum, an arts organization in New York, on a “privacy gift shop,” that will run through Sept. 23.

The New Museum, via Instagram

A view of the privacy gift shop in New York.

Mr. Harvey said his ultimate goal was to start a company to sell his line of privacy designs and products.

“This is something that I’ve wanted to do for a while,” he said. “There’s a big opportunity for anyone making privacy products to get their name out right now.”