Each 2-piece dowel set includes two wooden dowels with twill attached and wing nuts on each end. They are used in tandem with either the Needlework System 4 Wood Scroll Side Bars, or one of the Needlework System 4 Scroll Frame Holders. The side bars ARE NOT stretcher bars. Size: 3/4" Diameter Dowels sizes 6" to 26" are made of BirchDowels sizes 30" to 40" are made of Maple Tips: A running stitch of thread, or yarn will attach the canvas to the twill. Velcro may also be used and adhered to both the canvas and the twill to secure your piece. Dowels should be a size larger than your canvas measurement. For example if your canvas width is 19" you will need the 20" dowels. You can also turn your canvas sideways and use the dowel system with the length of the canvas instead.