Features horizontal locking mechanisms. LED module and optics are modular for ease of replacement. Front air intake design allows airflow past internal heat sink fins to rear exit vents while conserving a clean, thoughtful and seamless form. 18 watt isolated power supply sits within head to avoid further visual impact on track; dimmable digital logic controller operated in constant current mode. Field-replaceable proprietary 18 watt LED module. Three interchangeable optics: 15°, 25° and 40°. Holds up to two PAR16/MR16 lenses or louvers, sold separately.