Para-equestrian classification 4, 5, 6, 7, 12a/b, 13, 14, 21, 26a, 31a/b and 32 are allowed to have a whip which is held or used by a groom. Grade 1 drivers with Profiles 1, 2, 3, 4, 5, 6, 7, 9, 10a, 12a/b, 13, 14, 26a, 31a/b and 32 are allowed to have a brake operated by a groom. Grade 1 drivers with Profiles 1, 2, 3, 4, 5, 6, 7, 9, 10a, 12a/b, 13, 14, 26a, 31a/b and 32 are allowed to have a strap on feet or foot trough. Grade II is for riders who are higher functioning than Grade
9-orthoplex 9-orthoplex In geometry, a 9-orthoplex or 9-cross polytope, is a regular 9-polytope with 18 vertices, 144 edges, 672 triangle faces, 2016 tetrahedron cells, 4032 5-cells "4-faces", 5376 5-simplex "5-faces", 4608 6-simplex "6-faces", 2304 7-simplex "7-faces", and 512 8-simplex "8-faces". It has two constructed forms, the first being regular with Schläfli symbol {3,4}, and the second with alternately labeled (checkerboarded) facets, with Schläfli symbol {3,3} or Coxeter symbol 6. It is one of an infinite family of polytopes, called cross-polytopes or "orthoplexes". The dual polytope is the 9-hypercube or enneract. There are two Coxeter groups associated with the 9-orthoplex, one regular,