The Brown & Sharpe 599-750-10 1-2-3 blocks set includes a pair of 1” x 2” x 3” blocks, five 3/8-16 stainless steel socket head cap screws, and a hex key. The steel blocks offer rigidity and stability, and are oversized to allow normal tapping from .0001” to .0003”. With 28 holes, including five tapped 3/8-16, the blocks allow a range of different uses. Each block is ground and case-hardened to 50 to 60 Hardness Rockwell C (HRC) on all six surfaces, making all sides equally usable, and features squareness on all sides to .0001”. The surface finish is 6 to 16 microinches.

Blocks are used to check the squareness of machine fences, table saw blades, drill press chucks, and any other 90-degree angle found in industrial shops. Due to their weight, they are unlikely to inadvertently shift while in use. The holes can be used as stop blocks and make them easy to attach to drill press tables and table saw jigs. They can be used as a square for applications under 3 inches.

Brown & Sharpe was founded in 1833, had a major part in setting industrial standards in the United States, and has given its name to several standards, including a tool spindle taper, a worm threadform, and others. Brown & Sharpe was acquired by Hexagon Metrology in 2001, and has since focused on precision measuring equipment and metrology hand tools. The Brown & Sharpe line of coordinate measuring machines (CMMs), optical measuring systems, benchtop measuring machines, and precision hand tools offer consistent, high-quality design, construction, and performance. Brown & Sharpe has manufacturing facilities in North America, Switzerland, and China.