The ornamental design for a double nippleflowstream, as shown and described.
FIG. 1 is a top perspective view of a double nipple flowstream;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a rear elevation view thereof;
FIG. 4 is a left side elevation view thereof;
FIG. 5 is a right side elevation view;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The broken lines shown in the drawings illustrate portions of the double nipple flowstream that form no part of the claimed design.
The cutaway symbols illustrated in break lines in the drawings indicate a symbolic break in the length of the design for the double nipple flowstream indicating an indeterminate length. The appearance of any portion of the article between the break lines forms no part of the claimed design.