We claim the ornamental design for a top element of a protective cap for a syringe, as shown and described.
FIG. 1 is a perspective view at an angle from the front showing a top element of a protective cap for a syringe.
FIG. 2 is a perspective view at an angle from the rear showing the top element of a protective cap for a syringe.
FIG. 3 is a side view showing the top element of a protective cap for a syringe.
FIG. 4 is a front view showing the top element of a protective cap for a syringe; and,
FIG. 5 is a rear view showing the top element of a protective cap for a syringe.
The surface shading is for purposes of illustrating the character and/or contour of the surfaces of the claimed invention and forms no part of the claimed design.