GVM 672S-B Bi-Color LED Studio Video Panel 2-Light Kit (Black)The GVM 672S B Bi Color LED Studio Video Light features 672 LED bulbs for brighter lighting. The Master Slave control with 12 channels function allows you to set 12 different channels, and each channel can control more than 10 pcs of GVM same series video light. Just set one video light in master mode, and others in Slave mode. This means you can control about 120 pcs video light. User Defined Four Group Parameter You can define four different group