Slimmer design for easy installation, leaving more room for wires in the box. Automatically self-tests periodically to ensure GFCI protection. Child-safety black tamper-resistant shutters help prevent improper insertion of foreign objects. GFCIs incorporate lock-out functionality to protect against mis-wired line-load connections and GFCI circuitry damage. Wider button wells for easy TEST and RESET. Intuitive LED status indicators for trip and end of life states. Clean, modern industrial design with reduced top housing markings and neutral text direction on buttons.