Review : KDLITKER C8.2 , 1*18650 xhp50.2 flashlight

Btw
According to this test

The led gives 2200 lumen at 18w
And your math said the led recieve 16W, so i guess the lumen is about 2000-2100 lumen
With 10% loss of glass and reflector, maybe the number is nearly below 2000 lumen
Still impressive