This light has 3 main levels (High, Medium, and Low) and a beacon-strobe mode. Each main level can be programmed to one of its two sub-levels. The second sub-level of each main levels can be further programmed to different brightness levels.
LED: Cree XHP35 Neutral White (Nominal CCT 4500K).
Battery: One 18650 size (up to 69mm long) 3.6V-4.35V li-ion rechargeable.