Mercury - Quicksilver Flushing Attachment Engine Maintenance Tool Durable Composite 12612Q2. Overview. Anyone who's spent a few seasons on the water knows the easiest way to keep an outboard running strong is to flush it right. The Mercury Marine 12612Q2 Quicksilver Flushing Attachment makes that job simple. Designed for smaller Mercury and Mariner outboards, it connects cleanly to your water inlets and lets you flush the cooling system with a standard garden hose. Whether you're washing away sa