Here is an attractive one. The yellow gold plate case is a smaller 30MM size. It has a black dial with yellow gold applied hour markers and yellow gold hands. The back is Stainless steel with an L7 date code. The movement is a 17J 11AC with a L7 date code. I found a match to the case with a sub second called a Senator K with a white dial but no listing for a black dial. My guess it is a 1957 Bulova Senator variant unknown.
Case Serial No.