This is an OEM replacement ignition sensor for Mercruiser inboard engines from Arco. Fits: GM V-6 & V-8 Engines with Thunderbolt IV & V Ignition Replaces Part Numbers: MERCRUISER Ignition Sensor 87-892150Q02 MERCRUISER Ignition Sensor 892150A02 MERCRUISER Ignition Sensor 861780A2 MERCRUISER Ignition Sensor 91019A6 MERCRUISER Ignition Sensor 861780Q4 MERCRUISER Ignition Sensor 861780A4 MERCRUISER Ignition Sensor 91019A3 MERCRUISER Ignition Sensor 91019A2 SIERRA Ignition Sensor 18-5116-1 Warning: Product may contain materials cautioned by California Proposition 65