Canvas patterning ruler made of clear acrylic with holes every quarter inch Marking Circle: First insert awl through the point.Second, choose the desired hole. Then, insert the pencil in the hole and draw circle Folding Hems:Canvas patterning ruler has metal edge to smooth out the crease Adding Seam Allowance:canvas patterning rules has metal edge which can against the fabric,line up the ruler following the edge,choose your desired distance and draw the line on the fabric Various Distance Options:Canvas patterning ruler with holes located every 1/4 inch,which can allow your to draw a line or circle according to different distance options., Manufacturer: Colini01