Big Horn Brass Router Template Guide I.D. 9/32 in. O.D. 3/8 in. is a precision tool designed to provide controlled and accurate cuts when using a router with a pattern or template. This guide, made by Big Horn, replaces the Porter Cable 42036 model and attaches securely to the router base. It ensures that the router bit maintains a consistent distance from the edge of the template, allowing for clean and precise cuts into your workpiece. I for woodworking projects that require detailed and repeatable shaping, this brass template guide enhances your router's versatility and accuracy. Model Number: 19663