arc SBA2 format

[cualquiercosa327]

Hello, first give you thanks for this great program: it is very useful!
i am trying to mod Smile Basic 4 for Switch (jap version is the only available yet) changing the vibration files it included for the one i want.
All 62 bnvib files are included on an file with arc extension.

Curiously the other files of the game also have the same extension and i could extract them without any problem with sactool.
I have look it with a hexeditor and it seems this file is a SBA2 format.

data.zip