[SU(3)XSU(2)XU(1)]^2 and Strong Unification
  A supersymmetric model with gauge symmetry G_1 X G_2, where G_i=SU(3)_i X SU(2)_i X U(1)_i, is constructed within the framework of gauge mediated supersymmetry breaking. At the energy scale (10-100) TeV where the gauge symmetry breaks down to the Standard Model (SM), G_1 is strong and G_2 is weak. The observed gauge coupling constant unification of the SM is attributed to that of G_2. The messenger fields and Higgs fields just satisfy the condition that makes G_2 a realization of strong unification. The SM gauginos are predicted to be generally heavier than the sleptons and squarks. 
Chun Liu