Abstract: A device is for fastening a back on a middle of a watch. The back has a shoulder forming a cover arranged to cover entirely partly with the middle and a body arranged to rest in the middle. The device includes at least one pin integral with the middle, a seal mounted between the back and the middle. The back includes, near its periphery, at least one groove, the pin being arranged to slide in the groove between a first position, called the insertion position in which the back is free, and a second position called locking position in which the back is locked and positioned angularly relative to the middle. The groove includes at least one bump to form a hard point and increase the torque when the pin passes through the bump.

Abstract: A device for fastening a back on a middle of a watch, the back having a shoulder forming a cover arranged to cover totally or partially with the middle and a body arranged to rest in the middle, the device including at least one pin integral with the middle and a gasket mounted between the back and the middle. The back includes, close to its periphery, at least one recess, the pin being arranged to slide in the recess between a first position, referred to as insertion position wherein the back is free, and a second position referred to as locking position wherein the back is locked and angularly positioned in relation to the middle. The recess includes at least one bump to form a hard spot and increase the torque during the passage of the pin at the bump.

Abstract: An oscillating winding weight of a movement of a timepiece is mounted such that it rotates on an arbor of the movement. The oscillating winding weight comprises a main element conferring the overall shape of the oscillating winding weight, a heavy part allowing the weight to oscillate in response to the movement of the timepiece and the force of gravity, and a decorative element. The decorative element is a logo or initials and attached to the main element. The main element comprises a first material, the decorative element comprises a second material, and the heavy part comprises a third material. The third material has a higher density than the second material, such that the heavy part is heavier than the decorative element in order to position the decorative element in a predefined position.

Abstract: A device is for fastening a back on a middle of a watch. The back has a shoulder forming a cover arranged to cover entirely partly with the middle and a body arranged to rest in the middle. The device includes at least one pin integral with the middle, a seal mounted between the back and the middle. The back includes, near its periphery, at least one groove, the pin being arranged to slide in the groove between a first position, called the insertion position in which the back is free, and a second position called locking position in which the back is locked and positioned angularly relative to the middle. The groove includes at least one bump to form a hard point and increase the torque when the pin passes through the bump.