The Sightmark Quick Detach Battery Pack contains the battery pack within the system already. It features 10,000 MAH and will power all devices with USB formats. It includes a USB type A to micro USB cable.
Sightmark does not state whether or not the SightMark Quick Detach Battery Pack is waterproof/ or weather proof. The battery pack does feature covers for the USB input and Output ports to prevent unwanted dirt, dust, and debris from getting inside. I would recommend reaching out to the manufacturer for more information.
Sightmark does not offer specifics on battery life for an individual scope. The Sightmark Quick Detach Battery Pack has 10,000 MAH capacity which is a considerable amount of life/capacity for charging your optic. But for specific information I would recommend reaching out to the manufacturer for more information.
They must be left in. There is a power up period prior to the Sightmark external battery taking over. Therefore, the AA batteries must be in the scope.