  We propose an extension to recently developed Relativistic Lattice Boltzmann
solvers (RLBM), which allows the simulation of flows close to the free
streaming limit. Following previous works [Phys. Rev. C 98 (2018) 035201], we
use product quadrature rules and select weights and nodes by separately
discretising the radial and the angular components. This procedure facilitates
the development of quadrature-based RLBM with increased isotropy levels, thus
improving the accuracy of the method for the simulation of flows beyond the
hydrodynamic regime. In order to quantify the improvement of this
discretisation procedure over existing methods, we perform numerical tests of
shock waves in one and two spatial dimensions in various kinetic regimes across
the hydrodynamic and the free-streaming limits.
