This is the extension tube for the MC13 and E14 III flashlights. This will allow you to use an 18650 battery.
Material: Aircraft-grade Aluminum
Finish: Premium Type-III Hard-anodized Anti-abrasive finish
Dimensions: 82.2mm (3.24") length x 25.8mm (1.01") body dia.
Includes: Extension tube, stainless steel pocket clip, and stainless steel button
*We recommend using 18650 batteries that are button tops and are high-drain with 10A or greater.