I searched for a home center etc. but I could not find it. When I was in trouble I found something like Monotarou and found it as soon as I found it, so I was very much saved because I arrived the next day.
Even I who was not good at touching the machine could exchange easily. I thought for a moment that "it is expensive, but it is considerably better considering that I have never been exchanged since I bought it in 2005.
ER - IR 101, I bought it by mistake in model number here. What I needed was the ER - IR 100. I asked if I can exchange it once, but I bought it for opening again. At first I thought about putting the tape back in, but I gave up because it seems to be about twice space-saving. I was saved because I wore it immediately after 1 or 2 days. It is genuine and there is no problem in particular. It is somewhat difficult to get in the gaps of the head with wearing.