4,000 mAh, high charging capacity and resistant external auxiliary battery for solar recharging. Water resistant and silicone coated with a sporty design, especially designed for outdoor activities where there is no access to an electric charging source. Featuring dual USB output for charging two devices simultaneously and charging indicators. With a powerful SOS LED signaling light, designed for emergency situations. With aluminum carrying carabiner and including a resistant micro USB cable. Presented in an attractive design box.