This is a prism
whose cross-section is a rectangle, so it is equivalent to a cuboid.
In geometry, a cuboid or rectangular prism is a solid figure bounded
by six rectangular faces: a rectangular box. All angles are right
angles, and opposite faces of a cuboid are equal. It is also a right
rectangular prism.
The term rectangular or oblong prism
is ambiguous. Cuboid shapes are often used for boxes, cupboards,
rooms, buildings, etc. Cuboids are among those solids that can tessellate
3-dimensional space.