The ornamental design for a pantsupportbelt with straps, as shown and described.
FIG. 1 is a front elevation view of a pant support belt with straps showing my new design;
FIG. 2 is a rear elevational view thereof shown in use;
FIG. 3 is a right side elevation view thereof;
FIG. 4 is a left side elevation view thereof;
FIG. 5 is a top plan view thereof;
FIG. 6 is a bottom plan view thereof;
FIG. 7 is a front perspective view thereof; and,
FIG. 8 is a side view thereof shown in use.
The broken line showing of details in FIGS. 2 and 8 is included for the purpose of showing environmental portions of the pant support belt with straps and forms no part of the claimed design.