Mercury - Active Trim Kit (Without Trim Pad) 75-115 HP FourStroke Dual Engine 8M0129456. Overview. The Mercury Active Trim Kit (8M0129456) delivers full automatic trim control through your VesselView display, eliminating the need for a separate trim pad. Designed for dual-engine 75-115 HP FourStroke outboards (serial number 2B095049 and newer), it continuously adjusts both engines' trim angles based on RPM and boat speed for smoother acceleration, faster planing, and better fuel efficiency.. All