FIG. 1 is a perspective view of the end cap for a chromatography column assembly showing our new design. FIG. 2 is another perspective view of the end cap of FIG. 1. FIG. 3 is a front view of the end cap of FIG. 1. FIG. 4 is a top plan view of the end cap of FIG. 1; and, FIG. 5 is a bottom plan view of the end cap of FIG. 1.