[daveinaz]

You are right. I was looking at the fittings this morning and watched from the other end as I pushed in a small piece of PEX. I was stopping when I felt resistance as the PEX met the o-ring. I needed to keep inserting the pipe up past the o-ring until it seated at the end of the fitting. I was using the Watts quick connect fittings but the same thing applies as with the shark bites.