"A hunter, or in French “savonnette”, watch case has a metal lid that completely or partially covers the front of the watch, protecting the crystal. Half-hunter or demi-savonnette wristwatches, with a small circular window in the centre of the lid. A small area of dial and hands visible through the small window on a wristwatch."
"Wristwatches with hunter lids sometimes have the mark "Brevet 71363. Brevet means patent in French and the Swiss federal cross shows that this refers to a Swiss patent. The number 71363 is a Swiss patent granted to Charles Zurbrüegg on 23 June 1915 for a "Boîte-savonnette pour montres-bracelet" or hunter case for wristwatches. Zurbrüegg was listed as “fabricants de secrets” (meaning a maker of “secret springs”, a term used for the makers of the hidden springs of hunter watch cases), 17 Rue de la Gurzelen, Bienne."