vola boost

[Harry Muff]

the boost on the vola guitar sounds pretty good!  I was wondering how the engineering behind the volume push/pull booster works. these are some really cool looking guitars imo. it must have some type of cell phone lithium style battery on the back of a control plate or similar to powered pickups?

https://shop.volaguitar.com/collections/frontpage/products/vasti-surf-green