Portable battery for head mount display device

FIG. 1 is a perspective view of a portable battery for head mount display device showing our new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof;

FIG. 8 is a reference view thereof showing the state that the subject design can be attached to the head mount display device;

FIG. 9 is a reference view thereof showing an example of the usage of the subject design in a condition that the subject design has been attached to the head mount display device; and,

FIG. 10 is a reference view thereof showing an example of the usage of the subject design in a condition that the subject design has been detached from the head mount display device.

The broken lines in FIG. 8 , FIG. 9 and FIG. 10 show environmental structure only and form no part of the claimed design.