Sierra SAE 25W-40 4-Cycle Oil is blended with premium grade synthetic and mineral-based stock combined with superior designed additives formulated for the stress endured by sterndrive and inboard engines.• Superior corrosion protection• Advanced lubrication for reduction of wear to internal engine components• Outstanding friction reduction and wear protection• Removes thermal breakdown under high RPMs, extreme temperatures, and loads• Extensively tested for outstanding performance Outstanding friction reduction and wear protection Removes thermal breakdown under high RPMs, extreme temps, and loads Extensively tested for outstanding performance | 18-9440-2 SAE 25W-40 Synthetic Blend Engine Oil, Quart