We discovered Q&Q’s solar powered watches during Sight Unseen Offsite, a shoppable two-story exhibition that took place recently in New York City. Our team was instantly drawn to the colorful timepieces that sport a variety of textures and patterns sure to please even the most fashion-forward hipster.

Related: The Solar-Powered Seiko Astron Watch Even Boasts a Mini GPS Receiver

Then we learned that there was much more to love. Like the fact that the SmileSolar line features recycled materials and reduces waste by eliminating the need for a battery; the watch also made a not-so-brief cameo in Katy Perry’s latest music video, “Birthday.”

The watches transform the sun’s rays into time-keeping energy via a razor-thin solar panel hidden around the inside rim of the watch casing. According to the designers, an hour of sunlight gives the Smile Solar around three months of battery life–so as long as you go outside at least an hour a day, it will never run out of power! Best of all, when you purchase a Q&Q SmileSolar watch, a portion of the proceeds is donated to Table for Two to deliver school meals to hungry children in Africa and Asia.

All for just $40 a pop.

+Q&Q Smile Solar Watches