How to get RO2 concentration in saprc

Hi guys,

I’m wondering how to get RO2 conc. in models.cm3 by using saprc mech.
I know RO2 is straightforward in cb mech, but I cannot find the total peroxy radical concentration in saprc mech.

How can I calculate it? And the Molecular Weigh in saprc mech is same to the cb mech?

Thanks!!!