Name(required) Your email address(required) I'm not a historian. I'm not an authority on the SBDU. My knowledge about the SBDU has grown over the years since starting this blog. I aim to make everything I say as factual as possible, I do my research. There is a lot said about this small unit and lots of assumptions made about their frames but I try to give clear unbiased advice. If you have a question, just ask it here. (required) Submit Like this:Like Loading...