I miscalculated...current WIP UFO has almost 1200 2.5 squares! Tickled as I have 6 of the 13 rows sewn in pairs. I had to place fabrics in 2 sessions as the whole quilt wouldn't fit on the tablecloth design wall! I originally planned to use cotton backing with a row of blocks off set, but might use a minky type instead...I think I have a light tan that's big enough. Hope to get it down in the next week or so.