Point group Ci

"In crystallography, a crystallographic point group is a set of symmetry operations, like rotations or reflections, that leave a central point fixed while moving other directions and faces of the crystal to the positions of features of the same kind."

https://en.wikipedia.org/wiki/Crystallographic_point_group

Triclinic cell.
Schoenflies notation: Ci (S2)
Hermann–Mauguin notation: −1
Orbifold: x

OpenSCAD files included to make custom cells.

Further information:
https://www.staff.ncl.ac.uk/j.p.goss/symmetry/Ci.html