This is the main (U1) firmware for the Axpert King. It seems to have better support for PylonTech batteries than 71.80 or earlier main firmware versions.
It came with Display firmware (U2) version 02.00; I now believe that it is important to install that first.
Do not use with clones, only with genuine Voltronic Power manufactured machines. Otherwise, fault F90 is likely after a couple of months of runtime.