Many thanks for your quick response.

I use these routers in my camper van and mobile homes.
The idea is to attach a (single) ouside antenna each - maybe even with booster.
Sooner or later I will also want them to upgrade to dual band as well.
So the idea is basically to bring a long range wlan from outside into a mobile living space. Especially in the van (enclosed metal area) it makes a big difference to have an inside and an outside antenna.