The Starrett 289B Attachment for Combination Squares is a high-quality tool designed for precise measurements in metalworking and manufacturing. Made of durable steel and manufactured in the United States by the reputable brand Starrett, this attachment is specifically designed to enhance the functionality of combination squares. It provides accurate and reliable results for a variety of inspection and measurement tasks in CNC machining, metalworking, and industrial settings. This is new old stock never used