Ecopak Lens - 1700mm, Surface mounted batten luminaire, White powder painted metal body and steel spine, injection moulded polycarbonate High Rack lens. Options: LE3 - Lithium Emergency LS3 - Lithium Selftest LA3 - Lithium Autotest S - Switch Dimming D - Digital Dimming (DSI) A - Digital Addressable Lighting Interface (DALI) C - Bi-Level Dimming (Corridor Function) H - High Frequency Dimming (Analogue 1-10v) R21E - Reacta 21, On/Off R21C - Reacta 21, Corridor Mode* R44 - Daylight regulating and Occupancy Sensor RCS - Reacta-Control Wireless Sensor RLS - Reacta-Link Wireless Sensor *Bi-Level Dimming. Will only dim the luminaire to 10% during absence and brightout, it will not turn the luminaire off.