A portable power device may comprise a housing configured to contain an internal power supply and an attachment strap releasably connected to the housing for securing the device to an object or with space. The housing may comprise a top portion connected to a bottom portion by at least one hinge, and a gasket may be disposed between the top portion and the bottom portion to inhibit moisture from entering the housing. At least one clasp may be disposed on a side of the housing opposite the at least one hinge, the at least one clasp being configured to maintain the housing in a closed position without the use of tools. An attachment bracket may be provided that is releasably connected to the housing.