This is an AV-M30L5S 4K8K compatible TV booster from Abaniact. It came with the house when I bought it, but the internet and cable TV installers removed it and replaced it with something else, so I no longer need it. It's practically unused. (I didn't see them remove it, so I don't know if it was plugged in, but I've never connected it to a TV.) I'm not familiar with boosters, so please judge from the photos.