ISR (Formerly ISIS performance) colder temp thermostat for KA24DE and SR20DET. Good upgrade for High performance engines, where the ISR (Formerly ISIS performance) units opens at 60 deg celsius compared to factory 76.5 deg celsius. Cool down your motor before heat build up! Once the engine is fully warmed up the ISR (Formerly ISIS performance) thermostat will open up at a lower temperature than standard thermostats, also allowing the coolant to flow through the engine sooner thus reducing and maintaining cooler engine temperatures.