A bunker silo is the clamp where a farmer stores winter feed, and this wooden version does the same job at 1:32 scale. Low walls with angled buttresses, one open end to drive into: exactly where the tractor with the silage grab has to go.
Filling it is up to you. Maize from a bag, grass, a sheet of plastic with a few old tyres on top, or whatever happens to be around the house. Worth knowing: the silo is supplied empty. The maize, the sheeting, the tyres and the tractor in the photo are not part of it and only show what it can look like.
The whole thing is wooden and measures 46 x 38 x 5 cm. The walls are low enough to see over from a tractor and the entrance is wide. It works with farm vehicles from Siku, Britains and Universal Hobbies at the same scale.
A logical addition for anyone who already has a farm and a few tractors standing around and wants to extend the yard.