Each one measures approximately 27 and 1/2” by 12 and 5/8”.  Not sure what system they are compatible with.  One has a lip at the back that rises up a bit, other than the lip the measurements are the same as the others, 12 and 5/8” in depth.  That particular one has three dowels on each side, one of which is missing.  The other ones have two dowels on each side and all are present.  The tops are pretty clean, one has some scratches and scuffs.  The bottoms have a little more wear of that nature.  Two are a few shades darker than the other two, probably from exposure to light over time.  Please consult the shipping calculator for shipping costs, Thanks