It's 15k candela per their website: https://www.streamlight.com/en/produ...index/tlr-1-hl
I have both a x300U and the TLR-1 HL and honestly would have to nitpick to tell the difference. The X300U is more green and the TLR-1 HL is more cool white. The X300 as a more defined edge on the outer ring where the TLR does not. The TLR hot spot is slightly wider, but the intensity seems the same.