(The opinions below are those of a salesman, so…beware!)

GPO™ is a trademark of Gilbert Engineering who developed this connector. A military specification was written so the defense dept would have multiple sources for this connector. Only Gilbert can call this connector the GPO, though other suppliers feel their connector is equivalent & call it the SMP.Minor tolerance differences exist, be careful when substituting parts. Please call regarding your particular application, & compatibility between particular suppliers.