Thousands of Bolts has wonderful Flannels. Very nice quality. Select a color grouping then select fabric type, drop down menu and click flannel. I have ordered loads of flannel from them and their prices are more than resonable. Northcott, maywood Studio and Hoffman are all very nice flannels. Timeless treasures flannel can sometimes be on the thin side so I'm not sure I would recommend it for a rag quilt. I have not tried Henry Glass or South Sea Imports but I have always been very happy with both those manufacturers quilting cottons. Stay away from the wide back flannels, they are also on the thin side.
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