The truncated triangular prism is an undecagon obtained by truncation of a triangular prism. It has 18 vertices, 27 edges, and 11 faces. As a canonical polyhedron with unit midradius, its edges are of three different lengths,
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(1)
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(2)
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(3)
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with tallies of 12, 12, and 3 respectively.
The canonical truncated triangular prism has surface area and volume given by
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(4)
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(5)
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Its net is illustrated above.
The truncated triangular prism is also the polyhedron dual of the Goldner-Harary polyhedron, as illustrated above for the canonical versions of these solids.
