The PowerVault DSLR External Battery Pack for Sony NP-FW50 from Jupio is a portable 28Wh power supply for Sony DSLRs and video cameras that use an NP-FW50 battery.
It allows extended operation of the camera when stopping to change batteries is not an option. The included battery power cord fits into the camera body in place of the original battery to supply power from the pack.
The PowerVault also features a USB output suitable for charging most smartphones and tablets.