  In this letter we analyze the relative scales for the GUT and twin sectors in
the F-theory model discussed in Ref. \cite{Clemens-3}. There are a number of
volume moduli in the model. The volume of the GUT surface in the visible sector
{[}sector(1){]} (with the Wilson line GUT breaking) defines the GUT scale
$M_{GUT}\sim2\times10^{16}~GeV$ as the unification scale with precise gauge
coupling unification of $SU(3)\times SU(2)\times U(1)_{Y}$. We choose
$\alpha_{GUT}^{-1}\sim24$. We are then free to choose the ratio
$\alpha_{G}(2)/\alpha_{G}(1)=m_{1}/m_{2}$ with $m(1)$ and $m(2)$ independent
volume moduli associated with the directions perpendicular to the two GUT
surfaces. We then analyze the effective field theory of the twin sector(2),
which may lead to a SUSY breaking gaugino condensate. Of course, all these
results are subject to the self-consistent stabilization of the moduli.
