Stained glass is heavy. The size of the piece will merit the weight. A small window can use a 14.5" wide string of 4 birds with the weight only being 2 pounds. Larger windows where a grouping of 10 birds is displayed measures 19" x 11". The weight of a larger piece is nearly 3 pounds. The chain will correspond with the size of the panel, anywhere from 30" to 33" in length.