TARION Battery Back Pack Plate Adapter for Sony V-shoe V-Mount V-Lock Battery External / for DSLR Camera Video Light Mount Type: Sony V-shoe Mount. Can power an onboard camera light or broadcast accessory. Material: ABS Flame-retardant plastic and Aluminum Dimensions: Approx. 136X80X10mm/5.4X3.1X0.4'' It is a device which can connect the battery and videoing devices together.