13-670-5 SPI 1-2-3 Block Set
Matched 1-2-3 Block Set
Features include...
- Hardened Steel to RC 55-60, ground to surface finish 6-16 microinches.
- Squareness of all sides within 0.0001" per inch
- Five tapped holes (3/8" - 16), 18 untapped holes (3/8" dia.)