123 Blocks are ideal for precision layout and setup
- Each block is ground and case hardened on all six surfaces
- Surface finish 6 to 16 microinches
- Squareness on all sides to .0001" per inch
- 23 holes: 5 tapped 3/8-16
- Oversized to allow for normal tapping .0001" - .0003
- Case hardened to 50-60 HRC
- Set consists of a pair of 1 x 2 x 3 inches blocks, five 3/8 - 16 stainless steel socket head cap screws and key wrench
- Supplied in custom molded case
