Is Castrol Magnetec 5w40 a fully synthetic oil?

[VonJameson]

Castrol Magnetec 5w40 is a fully synthetic oil. Introduction to synthetic oil: Synthetic oil can be divided into semi-synthetic oil and fully synthetic oil. Fully synthetic oil contains no mineral oil components, while semi-synthetic oil contains some. The main differences between them are: fully synthetic oil has a wider temperature range and longer service life; for the same oil film requirements, synthetic oil can achieve this with lower viscosity, while semi-synthetic oil requires relatively higher viscosity to meet the same requirements. In other words, in the same working environment, fully synthetic oil can protect the engine with lower viscosity. Similarly, in the same working environment, fully synthetic oil has a much longer service life than semi-synthetic oil, so although the cost is higher, when considering the number of oil changes, it is not much more expensive than mineral oil. Characteristics of fully synthetic oil: Fully synthetic oil has better high and low temperature performance; has a longer oil change interval; and is suitable for more severe vehicle conditions.