Identical stackable containers specially adapted for retaining the same orientation when nested

Official title: {Identical stackable containers specially adapted for retaining the same orientation when nested, e.g. the upper container being fixed or slightly rotatable during the nesting operation (B65D21/041 takes precedence)}

B65D21/048 (Identical stackable containers specially adapted for retaining the same orientation when nested) appears on 36 US grants and 31 published applications in this corpus.