I have just purchased an XML-T6 torch and just using ordinary AAA batteries and I am quite pleased with the result. This torch is much brighter than anything else I have ever had.

However, I have just ordered 2 x 18650 batteries, but in the absence of any instructions whatsoever would like guidance on how they should be used. The torch was supplied with a nylon tube that I assume is for the 18650 batteries to sit in. I have not received the 18650 batteries as yet, but wonder whether I use one or two withe the nylon tube?