  We calculate the parallel upper critical magnetic field $H_{\parallel}(0)$
for an in-plane isotropic quasi-two-dimensional (Q2D) chiral triplet
superconductor at zero temperature, $T=0$. In particular, the ratio
$H_{\parallel}(0)/(|dH^{GL}_{\parallel}/dT|_{T=T_c}T_c) = 0.815$ is defined,
where $|dH^{GL}_{\parallel}/dT|_{T=T_c}$ is the so-called Ginzburg-Landau slope
of the upper critical magnetic field, $T_c$ is a superconducting transition
temperature at $H=0$. We show that the theoretically obtained above mentioned
value strongly contradicts to the experimentally measured ones in a candidate
for a chiral triplet superconductivity Sr$_2$RuO$_4$, which provides one more
argument against the chiral triplet scenario of superconductivity in this
compound. Our results may be useful for establishing chiral triplet
superconductivity in other Q2D candidates for this phenomenon.
