The MSDS, dated from 2017, indicates a large percentage of two types of PAO. Esters are not listed but usually are not in MSDS sheets. Redline oils are famous for containing a lot of esters, so have they significantly changed the base oils toward less esters and more PAO? One approximate indicator of esters is when the motor oil’s specific gravity is around 0.88 or more, which Redline has according to the MSDS. Another indicator of esters is when the oxidation level is tested in a VOA and the value is high (ex. 100), due to the oxygen atoms. The values I’ve seen in years past for Redline were around 100. I haven’t seen any recent results on that. Here is the MSDS: https://w3apps.phillips66.com/NetMSDS/ViewPDF.aspx?fileName=828863&Language=EN&IssueDate=9%2f19%2f2017&SubFormat=USDS