I looked at a new unused VP 540 damper I have here. It is more like B, except the metal doesn't connect the same way. The Roland has the metal as one connected piece, B looks to be two pieces. The other thing is the screen. I looked at mine under powerful magnification, and there is no pattern to the screen. It is very fine. I was told be a Roland tech once that the screen is the real thing that counts. It is the last protection your head has from chunks, even though they may be very very small. So if the screen is not as fine you run the risk of contaminants in the ink ruining the head.