Guido Storz invented a coupling for fire hoses in 1882. It has no male end and no female end. Any two couplings of the same size fit together, and a short turn locks them. A firefighter never has to look for the right end of a hose.
Some German fire brigades adopted it as early as 1887. It was patented in 1890. Sources disagree on whether that patent was Swiss or German. The Storz-Kupplung is still the standard of German fire brigades.