Nitecore TM36 Luminus SBT-70 LED NBP52 Rechargeable Battery Flashlight 1.1km

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2

Die is 3mm in diameter versus the 3.45 mm width of the XP-E2. That and 1800 lumens makes that 1.1 km claim sound possible.

Edit: XP-E2 die width is 1mm.