At this day (30/04/1935) hidden rivets were patented by M.Grunbaum. 1959 Levi Strauss & Co 9
At this day (30/04/1935) hidden rivets were patented by M.Grunbaum. 1959 Levi Strauss & Co 98 Battery St San Francisco Invitation Milton Grunbaum VP. It is a die-cut cowboy wit the invitation to the 50th Anniversary of Milton Grunbaum Vice President of Levi Strauss. -- source link