Yamalube 4-M FC-W (SAE 10W-30) oil meets the needs of modern outboard engines that operate over a wide range of rpms, under varying loads and in a range of marine conditions.This NMMA FC-W-certified oil provides maximum rust and corrosionprotection in advanced,four stroke outboard engines operating at varyingloads, in a range of marine conditions. Unlke automotive engines, marine outbords frequently operate at high rpms (5,000-6,000rpm) for extended periods of time. At these rpms, automotive oils can foam and lose lubricity which leads to wear. Yamalube 10W-30 oil prevents this with special anti-foaming agents, so engines can operate at high rpms all day long.Key FeaturesNMMA FC-W-certifiedProvides maximum rust and corrosionprotectionProtects during cold starts and at high temperaturesAnti-foaming agents maintain lubricity at high rpms