We investigate the suggestion that cosmic ray particles of energy larger than the Greisen-Zatsepin-Kuzmin cutoff are not nucleons, but stable, massive, supersymmetric hadrons, $S^0$s, which are $uds$-gluino bound states. Because the propagation range of $S^0$s through the cosmic background radiation is significantly longer than the range of nucleons, $S^0$s can originate from sources at cosmological distances.