Current Penrite has bugger all zinc.
Its fine if you just want it for a daily.
I use a combo of 50:50 Gibbs XP3 and XP6, to give a little more viscosity.
Need to be aware of what you mix with what.
Do a bit of research on Diesel oils, different ash and detergent formulations, and higher zincs.
You had better look up the Penrite site Jason, they have had some high zinc oils available for a while now