While I’m not too familiar with counter mortar systems, I do know that the crate is too small for the unit. That said, each crate might contain components to assemble. It’s not a small unit, but can be static on the ground, or mobile attached to a HMMWV.
Back in the day, counter battery was integrated in the bed of a deuce and a half.
The Vid shows three transport cases, the other two being about twice the size of the first.