Binary Tetraflexagon

**Figure 9:** The binary tetraflexagon has two cycles, each of which has two vertices in common with the other.
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**Figure 10:** Permutation of the squares along the strip for a binary tetraflexagon.
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**Figure 11:** Top side of the first level tetraflexagon cutout. The flexagon has six faces, so this cutout provides material for both of the sectors needed for the flexagon. Cuts should be made along the heavy lines, edges joined (using an extra little strip of paper taken from an unused spot) along the edges marked by dots. Together with the backside, the figure makes one individual flexagon.
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**Figure 12:** Bottom side of the first level binary tetraflexagon cutout.
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