Unparalleled Accuracy: Our latest precision ruler can provide unparalleled accuracy for your panel layout work. Just press the head to the desired angle, and then press the straight line. The head can be adjusted between 0° and 70° and is firmly locked every 5° (plus 22-1 / 2° and 67-1 / 2°), so as to provide you with an accurate reference angle and length respectively. Woodworkers Edge Rule: The secret to the TTKJ T-Square is the series of precisely machined indexing holes and the spring-loaded, tight-tolerance indexing pin that meshes with them. The pin snaps into place giving you the confidence to know it is spot-on accurate. Three Sizes Available: It is 10 inches, 15 inches, or 20 inches. Both edges of the blade are laser engraved with an inch scale in 1/32? increments. The graduations are held to a tolerance of ±.004" total accumulated error over the length of the blade. The thin, satin-finish stainless-steel blade is easy to read and minimizes parallax error. Perfect Woodworking Layout Tools: Even when you're not working with angles, this is a layout tool you'll reach for on almost every project. Does the blade feature the same exclusive? saw-tooth? design scribing notches found in our new Stainless Steel Precision Woodworking Squares. There's a notch every sixteenth-inch all along the blade. Just drop your pencil in the notch and slide the head along the edge of your stock for a perfectly parallel line.