An 18650 rechargeable (the approximate length of 2 CR123's) won't fit in the X1. As mentioned you need a 14500 (the approximate length of 1 AA). I have two 14500's and they are slightly too long for the X1. I accidentally pushed in the top of one of the batteries when trying it out. I think I got lucky and received a really bright one so there was not a big enough diffence to continue using the 14500. NiMH work fine and have better runtime than alkaline.
Which 14500s do you have? I think I am going to try Ultrafire's protected 14500 soon. Do you know if that'll fit.
I have some ultrafires comming, how do you guys know when to pull these out of your lights?? I am worried about over-discharging these when I get them..
Also, Are the rechargables higher volt than the non rechargables?
Don't get me wrong because I like AW and his products, but two AW protected 14500 cells from Lighthound are more than $26 shipped. Today I bought two UltraFire (gray) protected 14500 cells from the Ultrafire Shop for $9.50 shipped, or slightly more than one-third the cost.
Was the shipping price included in the $5.80 price they have listed. Because I thought shipping was included in the price displayed.
The Ultrafire Shop web site sells the UF protected 14500 (gray) for $5.80 including shipping. I got two from the Ultrafire Shop through EBay for $4.75 each including shipping.:twothumbs