Adjustment shaft

FIG. 1 is a front perspective view of the adjustment shaft, showing my new design;

FIG. 2 is a back perspective view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a back view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a left side view thereof;

FIG. 7 is a top view thereof; and,

FIG. 8 is a bottom view thereof.

The broken lines showing of the adjustment shaft are for the purpose of illustrating portions of the article and form no part of the claimed design.