In the requirements analysis phase, the specification can help specify the customer's vague requirements, and identify the conflicting, ambiguous, and unstated requirements. Hardware fastener industry even more so, the specifications of the products size are different, Jiaxing Goshen hardware's offerings have their respective size table, the following are some of the specifications we provided flat washer size chart:
| d | dc | h | |||||
| metric | max | min | max | min | metric | max | min |
| 1.6 | 1.84 | 1.7 | 4 | 3.7 | 0.3 | 0.35 | 0.25 |
| 1.7 | 1.94 | 1.8 | 4.5 | 4.2 | 0.3 | 0.35 | 0.25 |
| 2 | 2.34 | 2.2 | 5 | 4.7 | 0.3 | 0.35 | 0.25 |
| 2.3 | 2.64 | 2.5 | 6 | 5.7 | 0.5 | 0.55 | 0.45 |
| 2.5 | 2.84 | 2.7 | 6 | 5.7 | 0.5 | 0.55 | 0.45 |
| 2.6 | 2.94 | 2.8 | 7 | 6.64 | 0.5 | 0.55 | 0.45 |
| 3 | 3.38 | 3.2 | 7 | 6.64 | 0.5 | 0.55 | 0.45 |
| 3.5 | 3.88 | 3.7 | 8 | 7.64 | 0.5 | 0.55 | 0.45 |
| 4 | 4.48 | 4.3 | 9 | 8.64 | 0.8 | 0.9 | 0.7 |
| 5 | 5.48 | 5.3 | 10 | 9.64 | 1 | 1.1 | 0.9 |
| 6 | 6.62 | 6.4 | 12 | 11.57 | 1.6 | 1.8 | 1.4 |
| 7 | 7.62 | 7.4 | 14 | 13.57 | 1.6 | 1.8 | 1.4 |
| 8 | 8.62 | 8.4 | 16 | 15.57 | 1.6 | 1.8 | 1.4 |
| 10 | 10.77 | 10.5 | 20 | 19.48 | 2 | 2.2 | 1.8 |
| 12 | 13.27 | 13 | 24 | 23.48 | 2.5 | 2.7 | 2.3 |
| 14 | 15.27 | 15 | 28 | 27.48 | 2.5 | 2.7 | 2.3 |
| 16 | 17.27 | 17 | 30 | 29.48 | 3 | 3.3 | 2.7 |
| 18 | 19.33 | 19 | 34 | 33.38 | 3 | 3.3 | 2.7 |
| 20 | 21.33 | 21 | 37 | 36.38 | 3 | 3.3 | 2.7 |
| 22 | 23.33 | 23 | 39 | 38.38 | 3 | 3.3 | 2.7 |
| 24 | 25.33 | 25 | 44 | 43.38 | 4 | 4.3 | 3.7 |
| 26 | 27.33 | 27 | 50 | 49.38 | 4 | 4.3 | 3.7 |
| 27 | 28.33 | 28 | 50 | 49.38 | 4 | 4.3 | 3.7 |
| 28 | 29.33 | 29 | 50 | 49.38 | 4 | 4.3 | 3.7 |
| 30 | 31.39 | 31 | 56 | 55.26 | 4 | 4.3 | 3.7 |
| 32 | 33.62 | 33 | 60 | 58.8 | 5 | 5.6 | 4.4 |
| 33 | 34.62 | 34 | 60 | 58.8 | 5 | 5.6 | 4.4 |
| 35 | 36.62 | 36 | 66 | 64.8 | 5 | 5.6 | 4.4 |
| 36 | 37.62 | 37 | 66 | 64.8 | 5 | 5.6 | 4.4 |
| 38 | 39.62 | 39 | 72 | 70.8 | 6 | 6.6 | 5.4 |
| 39 | 40.62 | 40 | 72 | 70.8 | 6 | 6.6 | 5.4 |
