Features:

* 2600mAh high capacity capacity

* Genuine Sanyo cell from Japan
* Specially designed for high-performance flashlights and electronic cigarette
* Built-in over-charge and over-discharge protection circuit, maintain a long lifespan
* Short-circuit protection, ensure safety

XTAR 18700 2600mAh Protected Li-ion Battery

Voltage: 3.7V
Battery Capacity: 2600mAh                   Protection: Yes
Cell: Sanyo lithium cell inside
Size(mm): φ18.4±0.1mm(body Dia)x 69.2±0.5mm (Length)

Net Weight: 48g
Rechargeable

Notice: The above-mentioned parameters tested in Lab are approximate and may vary between flashlight/charger, batteries and environments.

Review:

http://www.candlepowerforums.com/vb/showthread.php?334950-Test-Review-of-Xtar-18700-2600mAh-(Black)

Reviewer's comment: The high voltage can be an advantage in smaller (i.e. 3-4 watt) lights where the battery replaces two CR123 cells.
It is a very good battery