The E3ZM-LS89H is a Photoelectric Sensor made by Omron. It is an analog, NPN output type, which has a range of 250 to 2500 millimeters and a sensing beam of an infrared LED and an optical receiver. It is IP67 rated, so it is dust-proof and waterproof. Additionally, it has a two-color LED used to indicate presence or absence of an object, and it also has a 316L stainless steel housing which makes it durable and corrosion-resistant.