The design is significant, as it is also found on a Roger Berry card. Note that Roger Berry were distributors of buttons rather than manufacturers. Either ‘Cygnet’ was branding used by the actual manufacturer of the buttons (?O.C.Rheuben), or it was yet another distribution firm. I have noted that Cygnet had an identical buckle one sold by Walker, and that Walker also was associated with Delphi. Further, Delphi got swallowed by Beauclaire. Very confusing. Perhaps Cygnet/Delphi/Walkers were all distributors rather than manufacturers. Perhaps they all distributed for General Plastics (and its predecessors) with some takeovers happening. General Plastics started to distribute buttons under their own name from the 1940s, so perhaps they had shares in some of the distributors?