not sure, I was told it is a bh-100, but it is set up backwards froma normal bh-100, what I mean is the pump is on the left instead of the right, looks like the ss series, but not. both of the standard bh-100, and bh-100ss work the same except the ss has a surface skimmer wich mine doesn't, but is set up like it with the pump on the other side. Making a short story long I'm not exactly sure.