Each canvas is made from faultless, finest grade cloth, painstakingly hand-stretched for outstanding tension, with expertly tailored corners. 16.93oz cotton canvas, stretched over heavy-duty solid pine wood frames. Primed with acid-free, pigment-rich Gesso primer. Includes archiving label to record details of your work, and the innovative patent-pending "prostretcher adjustable tensioner". .82" traditional depth Stretcher Bars.