Easily centers cutting tools for conventional lathe operations on either flat or rounded stock. For milling operations, makes indexing of squares, hexes, triangle, parallels and flats fast, easy and exact to 1/4 min. of angle. All surfaces are machined true to all other surfaces so can be used in literally hundreds of setup operations. Built-in level. Mfg: Brownells SPECS: Aluminum, silver, matte finish. 1-7/16" (3.65cm) x 1-7/16" x 1/2" (12.7mm).