Product review (4 stars): No instructions, but it works fine
Inexpensive, wired right up, but no instructions. I chased the wires from my old four wire connection to find which side was hot and it works fine. I am unsure if there would really have been an issue flipping them on 220, but I am glad I did not have to find out. Even if it doesn't matter, the instructions should tell you that rather than leave you guessing.