91307-PH7-660 O-RING (13.5X1.4) - Overview. The 91307-PH7-660 O-RING (13.5X1.4) is a critical sealing component designed for use in Honda marine engine systems. This precise rubber O-ring, with a 13.5mm outer diameter and 1.4mm thickness, ensures effective sealing to prevent fluid and gas leaks within the engine's cooling and temperature sensor systems. Manufactured to meet exact factory specifications, it plays a vital role in maintaining the reliability and operational integrity of Honda marin