Sierra's Premium Blend 25W-40 catalyst engine oil is specially formulated to meet the needs of 4-stroke marine engines with catalyst emission systems.
- Sierra premium blend catalyst compatible inboard engine oil
 - SAE 25W-40
 - 5 quart jug
 - Recommended for use with inboard and I/O marine engines with catalyst exhaust systems
 - Meets the requirements of modern 4-stroke recreational engines with or without emission catalyst systems
 - Developed specifically for the marine environment and the high running stresses marine engines encounter
 - Protects internal engine components from rust, corrosion, and from sticking piston rings
 - Premium blend features high detergency, anti-oxidants, and antiwear proprties
 - ZDDP anti-wear additive prevents phosphorus depletion and extends the emission catalyst life
 - Exceeds all 4-stroke requirements including FC-W and FC-W Cat compatible
 - NMMA FC-W certified
 - Replaces Bel-Ray 99730-BT4
 
