Gear shift drum assembly for a shift device of a transmission unit , in particular for motor vehicles, with a gear shift drum body which is rotatable about a gear shift drum axis , with a first shift element , with a second shift element , wherein a first and at least a second shift contour are formed on the gear shift drum body and extend over 360 degrees of the circumferential portion of the gear shift drum body , wherein the first and second shift contour are formed in an axial and/or radial direction, wherein the first shift element engages with the first shift contour and the second shift element engages with the second shift contour in such a way that these are displaced by means of the corresponding shift contour in the axial direction of the gear shift drum body by rotation of the gear shift drum body , characterized in that the gear shift drum assembly has a shiftable coupling device , in that the first shift contour has an optional path , and in that the optional path has a form of an axially locally widened first shift contour in the gear shift drum body , in that the first and the second shift element can be coupled by way of the shiftable coupling device in such a way that an axial displacement of the second shift element onto the first shift element is effected for the purpose of shifting to a neutral gear position, which is assigned to the optional path , wherein the axial widening of the optional path extends over an angular range, wherein, in this angular range, the first shift element is shifted between a gear stage and a neutral position in the optional path and the second shift element is shifted between a gear stage and a neutral position. with a gear shift drum body which is rotatable about a gear shift drum axis , with a first shift element , with a second shift element , wherein a first and at least a second shift contour are formed on the gear shift drum body and extend over 360 degrees of the circumferential portion of the gear shift drum body , wherein the first and second shift contour are formed in an axial and/or radial direction, wherein the first shift element engages with the first shift contour and the second shift element engages with the second shift contour in such a way that these are displaced by means of the corresponding shift contour in the axial direction of the gear shift drum body by rotation of the gear shift drum body , characterized in that the gear shift drum assembly has a shiftable coupling device , in that the first shift contour has an optional path , and in that the optional path has a form of an axially locally widened first shift contour in the gear shift drum body , in that the first and the second shift element can be coupled by way of the shiftable coupling device in such a way that an axial displacement of the second shift element onto the first shift element is effected for the purpose of shifting to a neutral gear position, which is assigned to the optional path , wherein the axial widening of the optional path extends over an angular range, wherein, in this angular range, the first shift element is shifted between a gear stage and a neutral position in the optional path and the second shift element is shifted between a gear stage and a neutral position. <EOS>