The DJI Zenmuse X9 Counterweight is used to help balance the Zenmuse X9 on a gimbal. The 11oz of counterweight compensates the weight of different lenses and accessories to keep the Ronin 4D’s gimbal stable. The Zenmuse X9 Counterweight is compatible with DJI Ronin 4D 4-Axis Cinema Camera 6K Combo Kit and the 8K Combo Kit and will not work with any other cameras or gimbals.