The Olight HDC cells are also rewrapped Sanyo NCR18650GA cells , So you have another option. They are protected and not cheap though. I would go with the Sony VTC6 or a Samsung 30Q if it will work. I had a married set of the Olight HDC cells for an X7, but one of them is no longer good so I broke them up and have them in other lights. Also they are made in China.