The focusing of HCl and DCl dimers was observed using a 2-m-long electrostatic hexapole field. The results indicate the existence of two types of species. The first is the homodimers, either the (HCl)-Cl-35-(HCl)-Cl-35 or the (DCl)-Cl-35-(DCl)-Cl-35, for which the data indicate a fast tunneling motion. The second is the heterodimers, (HCl)-Cl-35-(HCl)-Cl-37 or (DCl)-Cl-35-(DCl)-Cl-37, that do not show evidence for significant tunneling motion on the time scale of the experiment. In the case of HCl dimers, even at relatively high fields, only one species could be focused, the heterodimer. The electric dipole moments for both (DCl)(2) isotopomers were determined to be 1.5+/-0.2 D, which is the same value as observed for (HCl)(2).