I'm pretty sure it's balsa wood.
Balsa wood
A bridge made out of balsa wood and is an often used educational project.
Strength of joint
The most common method is with one or more screws or nails. Wood screws are especially made for the purpose. But screws and nails are not the only option. They can be bolted or pinned together, for example. with a bolt
An engineers vice firmly holds metal or wood so you can do whatever with it
a LOUVER is something that keeps rain out and lets air in. Aluminum is a metallic material different than wood.
Balsa wood is the lightest.
Yellow is the weakest therefore its the lightest blue is the strongest.
an arch bridge
walnut is the hardest and strongest kind of wood
Ozzy Osbourne after a cocaine binge.
balsa
The strongest wood on earth is Teak
the pambansang narra is the strongest tree in the pilipinas
Birch
His breath.
Balsa Wood
Usually Birch.