It’s hard to know what to call the new ROAMPROOF SOS 20K because it seems to do everything. First and foremost, it is a portable battery. With shockproof, waterproof and dustproof durability, the SOS 20K is designed to withstand some of the harshest conditions. This innovative powerbank keeps its charge for 59 hours via solar facilities and can charge up to 4 devices at once. Among several other useful capabilities, the SOS 20K also features an LED light with SOS signalling (hence the name). This charger won’t be available until February, 2016, but you can pre-order now.