Lufkin 626LN 6' x 5/8" Plumbers Wood Rule Red End Used for working with 45-degree elbows to eliminate figuring and chance of error Graduated on one side in black, inches to 1/16ths on both edges Graduated on other side in red, 45-degree scale inches to 1/16ths on upper edge only Turning rule from black to red gives corresponding 45-degree elbow Dimension Quantity: 1 per pack