Because the size of the old product and the dimensions (dimensions of the external form) were different, it was necessary to enlarge the mounting hole, and the time took more than expected. When the dimensions change, does the model number not change? It was a good study. The balance with the attached door got worse, but because the function did not matter ... · · · The exchange work itself is very simple and it will not take as long as 5 minutes. I think that it is a good product.