R & D Engine mounts are made specifically for marine applications and are designed to isolate drive train vibration from the hull. R & D engine mounts are shear loaded to provide stiff resistance fore and aft to absorb forward and reverse propeller thrust. Additionally, they are designed with vertical and lateral dampening to reduce vibration and noise. To help increase longevity of the mounts, R&D makes them with steel parts that are passivated and zinc plated to limit corrosion. The rubber element is covered by an oil shield to protect against petroleum-based products. To limit engine movement, the mounts are preloaded based on the combined engine and transmission weight. Key Features: Adjustable height Slotted mounting holes in the base make it easier to align drivetrain Fail-safe design features a steel rebound control washer Pre-loaded during manufacturing to restrict engine movement Zinc-plated and passivate