Model Compatibility: Fits the s100 vehicle model manufactured in the year 2015 as specified in the product title. Component Function: Serves as a replacement thermostat housing to restore the cooling system configuration for the listed vehicle. Specification Match: Designed to match the physical dimensions and mounting points required for the s100 2015 thermostat assembly. Installation Purpose: Intended to replace a damaged or worn housing unit on the s100 2015 without altering system. Fitment Scope: Applicable only to the s100 2015 model for direct substitution of the existing thermostat housing component.