SAE Grade 2
| Bolt Size | TPI | Proof Load (lbs) 1 | Clamp Load (lbs) 2 | Tightening Torque (ft lbs) | ||
|---|---|---|---|---|---|---|
| Galv+Waxed | Galv | Plain | ||||
| 1⁄4 | 20 | 1,750 | 1,313 | 3 | 7 | 5 |
| 5⁄16 | 18 | 2,900 | 2,175 | 6 | 14 | 11 |
| 3⁄8 | 16 | 4,250 | 3,188 | 10 | 25 | 20 |
| 7⁄16 | 14 | 5,850 | 4,388 | 16 | 40 | 32 |
| 1⁄2 | 13 | 7,800 | 5,850 | 24 | 61 | 49 |
| 9⁄16 | 12 | 10,000 | 7,500 | 35 | 88 | 70 |
| 5⁄8 | 11 | 12,400 | 9,300 | 48 | 121 | 97 |
| 3⁄4 | 10 | 18,400 | 13,800 | 86 | 216 | 173 |
| 7⁄8 | 9 | 15,200 | 11,400 | 83 | 208 | 166 |
| 1 | 8 | 20,000 | 15,000 | 125 | 313 | 250 |
| 11⁄8 | 7 | 25,200 | 18,900 | 177 | 443 | 354 |
| 11⁄4 | 7 | 32,000 | 24,000 | 250 | 625 | 500 |
| 13⁄8 | 6 | 38,100 | 28,575 | 327 | 819 | 655 |
| 11⁄2 | 6 | 46,400 | 34,800 | 435 | 1,088 | 870 |