Mercury – Active Trim Kit (Without Trim Pad) | Mechanical MerCruiser | Single Engine | 8M0129457Mercury Active Trim Kit (Without Trim Pad) Mechanical MerCruiser Single Engine 8M0129457 Overview The Mercury Active Trim Kit (8M0129457) automatically adjusts your trim angle through your VesselView display, removing the need for a physical trim pad. Designed for single engine mechanical MerCruiser 4. 5L and 6. 2L sterndrives (300350 HP), it continuously monitors RPM and boat speed to deliver smoother acceleration, quicker planing, and improved fuel