People who live in developing countries have always been concerned about water safety, but—as water crises in Flint, Michigan and parts of rural America show—fears for the cleanliness of what comes out of your faucet are not limited to remote villages in Asia or Africa.
Enter the Israeli company Lishtot (Hebrew for “to drink”). Its $50 TestDrop Pro, a patented device small and sleek enough to fit on a keychain, can tell if water is contaminated at the press of a button. It works without touching the liquid at all—instead it scans its electric field which, company scientists discovered, is different when contaminated by anything, from animal matter to chlorine to heavy metals. The device gives off a blue light if the water is safe to drink, and a red if not.
The device first went on general sale to the public in July, and CEO Netanel Raisch tells TIME that Lishtot is preparing to launch “testing as a service” in India in order to help the technology reach the people who need it most. “The way that we see it, it’s not just about making money,” Raisch says. “We built the company to help people.” —Billy Perrigo