I just recently bought a Nitecore LR12 Lantern (1 x 18650 / Cree XP-L HD V6). It claims 900 hours at 1 lumen for the lowest setting. I don't know if the claim is accurate but I'm currently testing that. I also own a Nitecore MH20 (also 18650 / Cree XM-L2-U2). That only claims 235 Hours at 1 lumen. Both flashlights claim a max of 1000 lumens. I know nothing about the science of LED lighting but can someone shed some light on the apparent huge difference in these claims.