The ornamental design for a seat part for a stroller, trailer for children or jogging stroller, as shown and described.
1. Seat part for a stroller, trailer for children or jogging stroller
1.1is a front perspective view of a seat part for a stroller trailer for children or jogging stroller embodying our new design;
1.2is a front elevation view thereof;
1.3is a rear elevation view thereof;
1.4is a left side elevation view thereof;
1.5is a right side elevation view thereof;
1.6is a top plan view thereof; and
1.7is a bottom plan view thereof.
The even dash-dash broken lines in the drawings illustrate portions of the seat part for a stroller trailer for children or jogging stroller that form no part of the claimed design. The dash-dot broken lines in the drawing illustrate boundaries of the claimed design.