CTS ACTON-1000 device, which is likely a fiber optic network terminal used for internet connectivity, specifically with ACT Fibernet services.
This is a model of an Optical Network Unit (ONU) or Optical Network Terminal (ONT). These devices are used in fiber-to-the-home (FTTH) networks to convert optical signals from the fiber optic cable into electrical signals that can be used by your devices (like computers and routers).