With Castrol EDGE, you benefit from all the advantages of our most powerful engine oil. By adding TITANIUM FSTT, we have doubled the thickness of the oil film to prevent oil film cracking and reduce friction.Find the right oil for your engine. CASTROL EDGE 5W-30 LL Castrol EDGE with TITANIUM FSTT stands for our best and most powerful hydrocarbon-based engine oils, which offer excellent performance even under extreme engine loads. The environmentally friendly use of available resources requires the development of smaller and more powerful, high-efficiency, low-consumption engines to enable low emissions. The moving engine components are not separated from each other.