Deb, I love mine. I made a longer one for my shoulders and neck. I just filled a section at the time, added a double line of stitching, then filled another section,more stitching, all way across until it was filled. That way, the rice stays more uniform and you don't have all the rice shifting to one end. Make this out of muslin, heat this part in microwave, then drop in pillowcase that folds over at end or velcros shut. That way, just wash pillowcase as needed. Mine is approx 14" long.
Love it, but keep giving mine away to someone and having to make another for myself.