The ornamental design for an inserter for an infusionset, as shown and described.
FIG. 1 is a perspective view of the inserter showing our new design;
FIG. 2 is a top plan view thereof;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a rear elevational view thereof;
FIG. 7 is a bottom plan view thereof; and,
FIG. 8 is an isometric view thereof.
The broken line showing of parts of the drawings is included for the purpose of illustrating use and environment and forms no part of the claimed design.