Hi infobel, Here’s the battery pack I got from Amazon: Talentcell 12V Lithium ion Battery Pack, 11.1V/9000mAh 99.9Wh Portable Power Bank, DC 12/9V and 5V USB Multiple Outputs. And here’s the Amazon link:
https://www.amazon.com/dp/B01337QXMA?re ... asin_title
For the power cord, I also ordered it from Amazon, and here is the description: 2PCS Male to Male 5.52.5MM Plug DC Power Adapter Cable DC Extension Cable 5.5 x 2.5mm Male Plug to 5.5 x 2.5mm Male Adapter Extension Cable 3.3FT/1M. And here is the link:
https://www.amazon.com/dp/B07WKB965H?re ... asin_title
As for how long the battery lasts, I’ve used it for hours without depleting much power, so I imagine it would last a pretty long time. If I can avoid it, I don’t like using the AC power adapters because if the adapter were to fail somehow and short circuit the full 120 volts into the power box, I would not want to be on the receiving end in case that happened, and therefore, the 12-volt battery pack avoids a potentially dangerous situation completely.
By the way, I finally decided to look inside the Tingler to see how it's built compared to the BTSTIM Professional 4-channel power box I also have. I've attached photos below, the first showing the Tingler interior, then followed by 2 photos of the interior of the BTSTIM Professional. As seen, the Tingler is carefully laid out with its well-crafted circuit board, while the BTSTIM Professional’s interior is quite cluttered with its 2 stereo audio amp circuit boards, its 4 output transformers, and its 4 current-limiting power resistors.
Looking at the interior of the Tingler compared to the interior of the BTSTIM unit, there are some similarities, such as the 2 output transformers, but I didn’t see the current limiting resistors as in the BTSTIM unit, so I was wondering how the Tingler limits the output current to avoid excessive currents in case the unit encounters a very loud sound from an inputting e-stim audio track.