Question: what is the difference between moen cartridge 1200 and 1225?
Answer: The Model 1225 is plastic, which if it becomes seized in the valve body, the cartridge can be broken and removed in pieces. He said the 1200 is more expensive because it's more rare than 1225, but the manufacturing cost of brass vs plastic is probably a factor. The 1225b is just bulk packaging of the single 1225.