Note: This product only works with our high quality Jupio square V-Mount batteries (BVM0010, BVM0011, BVM0012, BVM0013). Jupio's latest product innovation gives you the ability to power your V-mount devices without fear of running out of power. The BVM0255 V-Mount plate allows you to use 2 Jupio square V-Mount batteries sequentially instead of 1. With the ability to hot swap the batteries, you can change the empty battery while continuing to film because of the second full battery. The BVM0255 plate is also equipped with a D-tap output interface for additional accessories and an LED indicator for the battery status. In addition to its use as a power supply for your V-mount device, it can also be used as a battery charger using either the V-Mount terminal or the bidirectional D-tap port. When the battery power is too low or if a battery is removed during the discharge process, the V-Mount Hotswap adapter plate will automatically switch to the other battery for power supply. During the switching process, the electrical device will not switch off and can therefore be used normally. The lower capacity battery will always be discharged first ensuring you have maximum power when you need it most.