I finally took a picture of the 3 12ga 870s. We also have a 20 ga youth model but not in this picture.
The white labels on both sides indicate LOADED and type of rounds (00 Buck, Sabot and Rifled Slugs).
Top to bottom:
870 Express Magnum with fully rifled rifle sighted barrel (2 x OO Buck and 5 x Sabot)
870 with bead sight (6 x 00 Buck)
870 (NFA AOW) with MagPul Forend, AFG2 and Mesa 4-shot carrier (4 x rifled slugs)