Adidas has released solar-powered headphones that constantly charge from any light source. They theoretically run forever in full sunshine.

The RPT-02 SOL is not the first set of solar headphones, though its by far the biggest brand to use the technology. As you might expect from a fashion brand, the solar isn’t harvested through garish panels but rather is built into the surface of the headband. It uses several photovoltaic sheets that are each only 100 atoms thick.

The battery can charge from both natural and artificial light sources including indoors. On a sunny day outdoors it should charge at least as quickly as it discharges during playback, so would theoretically run indefinitely. With indoor light it will top up the battery when not in use.

The battery capacity means the headphones could run for 80 hours in complete darkness and there’s a backup option of a USB-C charge that fills the battery in around two hours.

For those interested, the RPT-02 SOL will be available for purchase online on August 23rd.