>The decimal looks OK to me (but don't take my word for it :-})
>I'm not sure about char. In .NET char is a two-byte structure whereas (I think? ) char in SQL is one byte. I've no idea how well those play together....

Other developers used SqlDbType.Varchar. I need to be sure I am correct in my thinking I need to use Char if the field is Char - would be nice if someone can deny or confirm.

In the meantime, I'll try running profiler and see how the parameter is being passed to SQL.