zebralight h600 mk iv 18650 xhp35 cool white headlamp zebralight cree xhp35 cool white led. nominal cct: 5700k, cri: 70+. user selectable levels: 3 main levels (high, medium and low). each main level can be programmed to one of its two sub-levels. the second sub-level of the each main levels can be further programmed to different brightness levels. light output - high: h1 1616 lm or h2 1010 lm/579 lm/305 lm, medium: m1 147 lm or m2 65 lm/26.4 lm/9.9 lm, low: l1 3.4 lm or l2 1.06 lm/0.3 lm/0.08 lm, beacon strobe mode: 0.2hz beacon at low / 0.2hz beacon at h1 / 4hz strobe at h1 / 19hz strobe at h1. operating voltage range: 2.7v - 6.0v. battery: one 18650 size (up to 69 mm) 3.6-4.35v li-ion rechargeable. batteries are not included in the package. parasitic drain: negligible (much less than the self discharging of a battery). beam type: 80 degree spill, 12 degree hot spot. dimensions - head diameter: 0.95 inch (24.2 mm), length: 3.85 inch (97.8 mm). weight 1.4 oz (39 gram), 3.0 oz (84.6 gram) with zl635 battery, 4.4 oz (124.6 gram) with zl635 battery and headband. features pid thermal regulated outputs (three highest output levels). builtin battery protections with continuously monitored temperature, current, and voltage, plus a (2.7v) low voltage cutoff. battery capacity indicator (led flashes 1-4 times, 4 short clicks to start). automatic stepping down from high to medium, and from medium to low when battery capacity is low. durable electronic soft-touch switch. sealed and potted led driver circuitry. tempered optical grade glass. orange peel textured reflector. battery reverse polarity protection.