The ornamental design for a composite plasticsbridgeunit, as shown and described.
FIG. 1 is a perspective view of a composite plastics bridge unit, showing my new design;
FIG. 2 is a side view thereof, the opposite side view being the same;
FIG. 3 is a top view thereof;
FIG. 4 is a bottom view thereof;
FIG. 5 is an end view thereof, the opposite end view being the same; and,
FIG. 6 is an enlarged fragmentary section, taken on the line 6—6 of FIG. 1. A middle portion is broken away in FIGS. 1–4 to disclose indefinite length.