These binoculars have automatic focussing but weigh a ton.

Given the source, U boat surface targeting binoculars, maybe ?

IIRC these were clamped into a fixture in the conning tower that fed directional infromation from where the binoculars were pointing relative the U boat heading down to the plotting / control room inside the boat - there is a scene in "Das Boot" of a surface attack showing something along those lines. Weight would not have been an issue in such an application.

Not sure how much value would be added to a historical collectible item like this to have them functional. Maybe actually devalue them to have them interfered with, as items such as the "grip" coverings may have to be removed to access fixings for dismantling and alignment.

Suggest treading carefully and taking specialist advice.

Nigel B.