LUBEN FS Series is a trunk piston engine oil designed for use in medium speed diesel engines operating on residual fuels in marine, power generation and industrial applications. The superior additive technology used in this oil provides excellent engine cleanliness & wear protection under different operating conditions. This oil is available in 40 viscosity grades with a BN (Base Number) 40 KOH/g. These oils exhibit a high degree of water tolerance and have better water separation and base retention properties. These oils meet the performance requirements of API CF.