Mercury - Spark Plug NGK BR7HS-10 Series Marine-Grade Metal & Ceramic 8M0181925. Overview. There's a certain confidence that comes from hitting the ignition and hearing your engine fire instantly, cleanly, and without hesitation. It's that little moment-whether you're drifting near the mangroves or gearing up for a long run offshore-that reminds you your boat is ready. The Quicksilver 8M0181925 NGK BR7HS-10 Spark Plug helps deliver that feeling every time. Built for dependable starts and steady