OTTO Excavator Parts Npr75 4Hk1Tc Thermostat Shell 8973299140 897329-9140 8-97329914-0 For Isuzu This OTTO Excavator Parts Npr75 4Hk1Tc Thermostat Shell with part numbers 8973299140, 897329-9140, 8-97329914-0 is designed for Isuzu engines. It helps regulate and maintain the optimal operating temperature, crucial for engine performance and efficiency.