The ornamental design for a low profilegasblock, as shown and described.
FIG. 1 is a top view of a low profile gas block according to my design;
FIG. 2 is a front view thereof;
FIG. 3 is a side view thereof;
FIG. 4 is a back view thereof;
FIG. 5 is a bottom view thereof;
FIG. 6 is an isometric view thereof; and,
FIG. 7 is an isometric view thereof installed on a rifle.
The broken lines having repeated short dashes in the Figures are for illustrative purposes only and form no part of the claimed design. The shade lines having a combination of long and short lines in the Figures show contour and not surface ornamentation.