I have a 12" long one covered with one layer of batik & stitched closed at each end. I use it for individual blocks. The other one is 48" long and 1 1/4" diameter after the closet pole was cut down the middle, bare, not covered with any fabric. I prefer the bare one. It is so handy when pressing a long seam where there are so many small intersecting seams. You are so right about how helpful it is. It also keeps the seams from curving as you press.