Abstract: A watch case includes a case middle made of plastic or electroformed material and a crystal. The crystal or the case middle includes elbowed catches that are each insertable in a bayonet fitting in a recess of the case middle or the crystal. The case also includes a rotation stop angularly securing the case middle and the crystal in an angular position such that a part of each catch is frontally locked behind a holding surface of the case middle or of the crystal. The rotation stop is frontally snap-fitted on the case middle and/or the crystal by snap-fit fingers that cooperate with a complementary stop surface of the case middle and/or of the crystal.

Abstract: Watch case (1) comprising a case middle (2) made of plastic or electroformed material and a crystal (3), the crystal (3) or the case middle (2) comprises elbowed catches (4), each insertable in a bayonet fitting in a recess (5) of the case middle (2) or the crystal (3), and the case (1) includes a rotation stop means (6) angularly securing the case middle (2) and the crystal (3) in an angular position wherein a part of each catch (4) is frontally locked behind a holding surface of the case middle (2) or of the crystal (3), this rotation stop means (6) is frontally snap-fitted on the case middle (2) and/or the crystal (3) by snap-fit fingers (61) which are comprised therein and which cooperate with a complementary stop surface, of the case middle (2) and/or of the crystal (3).

Abstract: An instrument for counting duration for differentiated phases, including: plural mechanisms for recording a time duration, each actuatable, for activation and deactivation thereof, by a first controller; a general controller for controlling, from an inactive position in which all the recording mechanisms are deactivated, activation of only one of them, selected by a selector, and for again controlling, at a final moment, deactivation of all the recording mechanisms; a switch configured, during a command for activation of one of the recording mechanisms, to trigger the deactivation of all other recording mechanisms and to save totality of the recorded times, counted on each of the recording mechanisms. The selector is configured to be controlled by a user or/and by a measuring mechanism or/and by a signal to trigger the activation of one of the recording mechanisms.