The Honeywell HOA0861-T55 is a transmissive sensor designed for accurate position sensing in a variety of industrial applications. It combines an infrared emitting diode with an NPN silicon phototransistor, encapsulated in a durable black thermoplastic housing. Key features include four mounting configurations, a choice of detector aperture, and options for opaque or IR transmissive housings. The polysulfone housing provides resistance to chlorinated hydrocarbons and ketones, making it suitable for harsh environments. This sensor is ideal for applications requiring reliable object detection and position resolution, such as automated machinery, conveyor systems, and security devices.