The ornamental design for a two-piece watch set, as shown and described.
FIG. 1 is a top right perspective view of a two-piece watch set showing my new design in an assembled condition;
FIG. 2 is a top plan view thereof;
FIG. 3 is a bottom plan view thereof;
FIG. 4 is a right side elevational view thereof;
FIG. 5 is a left side elevational view thereof;
FIG. 6 is a front elevational view thereof;
FIG. 7 is a rear elevational view thereof;
FIG. 8 is a bottom perspective view thereof in an exploded condition;
FIG. 9 is a top perspective view thereof in an exploded condition; and,
FIG. 10 is a top perspective view thereof in a partially exploded condition.
The structural features and indicia depicted by broken lines in the drawings have been shown for the purpose of illustrating portions of the two-piece watch set that form no part of the claimed design.