I ventured into the 18650 world with the purchase of a SolarForce L2M and a low voltage (.8-4.2v)XP-G module...and at the same time purchased a Nitecore D2 (two slot) charger... as Hikermore commented, it works well with my AAA and AA Eneloops as well as the 18650...in hind site, I should have purchased the 4 slot version....I attempted to standardize my batteries to AA Eneloops after the 9 day outage in 2004...while I still have a 12vdc trolling motor battery for my TV, and a few Ds for the ceiling fan and larger MagLights, the AA Eneloops are working in most all of my non weapon lights which are still primary 123s