Shield boss, height without stud on top, 6.2cm, diam. 15cm. Low concave dome, with top knocked off, marked angular carination above indented waist, and flat flange width 15cm. Flange has five disc head rivets, one with shank surviving - slight traces of wood and leather on underside. This boss is in remarkably good condition: solid, smooth, stable, and very different from all the rest. Different site and conditions? N. Thames?