Product DetailsSierra 18-1989 Thermostat Housing Stainless Steel for MerCruiser Sterndrives. Replaces: Mercury Marine 861006A replaces: Mercury Marine 87290A4
Sierra provides premium-quality aftermarket replacements for over 6,000 marine parts, tools, and components. Sierra products are engineered to meet or exceed OEM standards, and stand up in harsh marine environments. Every new Sierra part comes with a limited lifetime warranty that covers the useful life of the product against any defects in workmanship and materials.