Swiss leather holster for model 1929 Ordnance Revolver (model 1882/29). Black leather.
Inside compartment of the holster features loops for holding five spare cartridges. Black coloring on the shoulder sling is worn.
No leathermaker stamp nor Swiss military inspection stamps found on the holster, so it is likely that this is a commercial holster.
Photos depict actual holster for sale. Luger shown not included, but these revolver holsters seem to be able to also retain a Luger pistol.