The chords form 200 central hexagons (25 sets of 16, with each hexagon in two sets), 10 of which cross at each vertex (4 from each of five 24-cells, with each hexagon in two of the 24-cells). Each set of 16 hexagons consists of the 96 edges and 24 vertices of one of the 25 overlapping inscribed 24-cells. The chords join vertices which are two edges apart. Each chord is the long diameter of a face-bonded pair of tetrahedral cells (a triangular bipyramid), and passes through the center of the shared face. As there are 1200 faces, there are 1200 chords, in 600 parallel pairs, apart.