3G refers to 3Gb/s serial digital video. At twice the bit rate as HD SDI, 3G can transmit 1080p (50 or 59.94) and 4:4:4 RGB signals on a single cable. For example, The BrightEye 57’s 3G test signals are useful for facilities that are installing 3 Gb/s routers and signal distribution. BrightEye 57 is compliant with SMPTE 424M and 425M and has support for both Level A and Level B. 3G Level A is used for uncompressed 1080p 50/60 signals, useful in broadcast and satellite. 3G Level B is used for uncompressed 1080i 4:4:4 and is useful in post production.