These are the nailess sawtooth picture hanger for use on softwood frames. The nailess hangers measure 2.5 cm(1 inch) in length by 8 mm(5/16 inch) at the widest point. Entrance prongs measure 9 mm(3/8 inch)in length. Low profile, zinc plated steel hangers. Bear Woods Supply offers quality self-fastening nailess picture hangers for your wood working projects!