Masaki, the Seabands and the ReliefBand are two different things. Seabands are what DougW uses. They are elastic bands with the pressure point, same theory as the ReliefBand. However, they are inexpensive and have no working parts, they are simply pressure bands. I would try them first. I have used them in the past, but I suppose I am the rare case where they weren't so effective. The ReliefBand looks like an actual watch, battery operated, and sends a little "shock" every four seconds or so. It is fairly expensive, I paid $80 for it on the Voyager. Their website may have it cheaper.
But, it works like a charm!!!!