21 Pin Locking Angles: A unique angle lock features a stainless steel arm that easily glides on a precision machined track that allows you to lock in your angle using a quick push index plunger button for precise and repeatable cuts. Three Level Vials: Reduce how many tools you need on the job by using the three level vials, which includes a bullseye vial, on the locking arm that allows you to check for level and plumb quickly and easily. Durable Construction: The Britton Square is made from high-quality materials, including aluminum and stainless steel with an anodized coating and all markings are laser engraved. Designed to withstand heavy use and resist warping, cracking, and breaking. Versatile Design: While the Britton Square can be used as a traditional speed square, it’s unique features allows it to be used in a variety of ways, including as a saw guide, a protractor, a level, pitch finder, angle finder, plumb bob, straight-edge and circular scriber. 2.5mm allen torque spec- 10 in-lb max.3mm allen torque specs- 19.2 in-lb max.Construction pencil included with sharpener. 3 Grey and 3 Yellow refills 2.8mm, Manufacturer: Britton Tool