As far as I know, "Black Panther" branded AGM
batteries are no longer marketed.
The Black Panther battery
was actually sold by a company called Crischell Automotive Products located on Colorado. The line was called the Predator series. Crischell obtained the raw batteries from Hawker Energy Products.
They took the Hawker "Genesis" line of batteries, fit them with brass lugs and resold them under their own name.
These batteries are based on the "Starved Electrolyte" type (AGM, or Absorbed Glass Matt), where the battery
is produced using an inert mesh to hold a bare minimum of electrolyte (i.e. acid) in contact with the lead plates
Because of this "acid-starved" condition, this type of battery does not normally perform well in heavy, deep discharge applications.
“Odyssey” & “Optima” AGM