The rolux rl-bmg battery holder is designed to power your blackmagic ursa mini. you need to connect a v-mount battery (not included) to the rl-bmg to create a reliable solution. v-mount batteries are known for their long battery life, which allows you to get the most out of your rl-bmg. the v-mount batteries are secure in place, but they can be disassembled with one push on the button. Usage rl-bmg Use the supplied screws to mount the rl-bmg onto the blackmagic ursa mini. preparations have been made for both the rl-bmg and the camera for quick and easy assembly. only one cable needs to be connected, that’s all. the rl-bmg is suitable for all common v-mount batteries. on the side of the rl-bmg is a d-tap connector to power your favorite accessories (for example, a led lamp).