  In this paper we extend three results about polycycles (also known as graphs)
of planar smooth vector field to planar non-smooth vector fields (also known as
piecewise vector fields, or Filippov systems). The polycycles considered here
may contain hyperbolic saddles, semi-hyperbolic saddles, saddle-nodes and
tangential singularities of any degree. We determine when the polycycle is
stable or unstable. We prove the bifurcation of at most one limit cycle in some
conditions and at least one limit cycle for each singularity in other
conditions.
