The ornamental design for a pneumatictool casing, as shown and described.
FIG. 1 is a perspective view of a pneumatic tool casing showing my new design;
FIG. 2 is a top plan view thereof;
FIG. 3 is a front elevation view thereof;
FIG. 4 is a rear elevation view thereof;
FIG. 5 is a left side elevation view thereof;
FIG. 6 is a right side elevation view thereof;
FIG. 7 is a bottom plan view thereof; and,
FIG. 8 is a perspective view thereof, wherein a pneumatic tool is engaged.
The broken lines shown in the drawings illustrate environmental structure and portions of the pneumatic tool casing that forms no part of claimed design.