Made in the USA
This is the identical thermostat as the infamous “Robertshaw 333-” thermostats. The Track Boss thermostat is manufactured by the same company who currently make the current Robertshaw thermostats.
If you have a 351C engine, make sure you are using the by-pass plate. (this plate is NOT used in a 351M/400 blocks) You can add the by-pass plate and save ($49 for the set).