Sierra 18-3631 Thermostat with Housing for Mercury 892864T04 Thermostat with Housing for Mercury Replaces: Mercury-892864T04 Sierra Part Number 18-3631 Fits: 135-300 Verado All Sierra parts qualify for and are covered under Sierra's Industry Leading Customer Satisfaction Warranty Before Ordering, Please Verify this is the Correct Part for your Application. For Assistance, Please Call Sierra's Tech Support at 1-877-663-8396