L’Oréal has announced a wearable device that measures your exposure to ultraviolet radiation that can seriously damage your skin and eyes and potentially cause skin cancer. The La Roche-Posay My Skin Track UV sensor is designed to clip onto your clothes or bag, and it relies on NFC rather than Bluetooth to transmit its data, meaning it doesn’t require a battery to function. L’Oreal previously introduced a similar sensor that attached to your fingernail.

Despite the dangers of UV radiation, it can be very difficult to know exactly how much you’re being exposed to. UVA rays can penetrate clouds and glass, which means you’re probably exposed to them more than you think. L’Oréal’s sensor has the potential to educate people about how often they’re being exposed, although it won’t solve the problem of people not using enough sunscreen in response.

Once your phone has the UV data, it can integrate it into Apple’s HealthKit if you’re using an iOS device. There will also be shortcuts to purchase skincare products from L’Oréal’s skincare brand La Roche-Posay within the app.

The sensor measures UVA radiation, the variant that penetrates deeply into your skin and chiefly causes skin aging and wrinkling. Wired notes that it then uses this data to estimate UVB exposure. Although both kinds of UV radiation are believed to contribute to the risk of skin cancer, it’s UVB that has the bigger impact here, also causing your skin to burn.

The sensor will cost $59.95, and it’s available in the US exclusively at Apple Stores and on its website starting today. The companion app is available for both iOS and Android.