I picked up the Poseidon Pro Power Bank for my emergency kit and it has been a solid choice. It is waterproof and drop-proof, which gives me real peace of mind when I am out hiking or when the power goes out at home. What surprised me most is how long it holds a charge; I left it in my bag for months and it still had plenty of juice to power my gear. It is not the lightest option out there, but for something this tough and reliable, that is a fair trade. It does exactly what it promises.