SPI Gage Block Set - Rectangular Blocks, 81 pc. Set, Grade Economy - 30-912-0
- Grade 0 and Grade AS-1 accuracy meets or exceeds Federal Specifications B89.1.9-2002
- Certificate of calibration traceable to NIST included in each set and each individual block
- Grade economy shop accuracy approx. ±.00005"
- All sets are supplied in attractive fitted case
Tolerances in Microinches
| | Grade 0 | Grade AS-1 | Economy |
| 1" and less | + 4 - 2 | + 8 - 4 | +50 - 50 |
| 2" | + 8 - 4 | +16 - 8 | +50 - 50 |
| 3" | +10 - 5 | +20 - 10 | +50 - 50 |
| 4" | +12 - 6 | +24 - 12 | +50 - 50 |
81 pcs. Set
- 9 Blocks - 0.1001 thru 0.1009" 0.0001" steps
- 49 Blocks - 0.101 thru 0.149" 0.001" steps
- 19 Blocks - 0.050 thru 0.950" 0.050" steps
- 4 Blocks - 1.000 thru 4.000" 1.000" steps