The Boulder 30M collect 30 watts of power from the sun, and stores power with the Extreme 350 or other Goal Zero power packs (sold separately) for use anytime. The solar panel can charge the Extreme 350 in about 12 hours. Use the stored solar power with your USB or 12V devices. The Boulder 30M is portable, but can be permanently installed. On the mountain or at the beach, the Boulder 30M goes wherever you do to help charge your power packs, to keep you connected to your digital life.