GVM 520S-B Bi-Color LED Studio Video 2-Light Panel KitGVM 520S B Bi Color LED Studio Video Light Panel Kit is the newest version and comes with functions such as the Multi function control and User defined four group parameter. Multi Function Control Through Active standby Mode and 12 channels function, you can set 12 different channels, and each channel can control more than 10 pcs GVM same series of video light. Only need to choose one video light in master mode, and others in Slave mode. This means