I don´t think that the Boxers modules can be used on the Lynx. The Lynx is modular but it requires more time and the components seem to be stand alone and having to be joined rather than a complete mission module.
It is said though that they can be exchanged in around 8hrs and under field conditions. Right now there are only two versions the IFV and the APC.
The Rheinmetall’s future-oriented infantry fighting vehicle (IFV) was designed to crack down on the challenges of the amorphous multi-domain conflict scenarios of today and tomorrow.
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