Limit plug gauge (Plain Gauge) is a pair of gauges having dimension of maximum and minimum limit size of hole to assure the interchangeability of the engagement between hole and shaft.
| Nominal Size ød exceeded~less | GO | NOT GO | Under Neck | Length | Handle Length | ||
| K1 | L1 | K2 | L2 | m | L | ||
| 1 include ~ 2 less | 6.5 | 22 | 4.5 | 20 | 5.5 | 62 | 40 |
| 2~3 | 6.5 | 22 | 4.5 | 20 | 5.5 | 62 | 40 |
| 3~6 | 8 | 26 | 6 | 24 | 6 | 74 | 48 |
| 6~8 | 10 | 32 | 7 | 29 | 7 | 87 | 56 |
| 8~10 | 10 | 32 | 7 | 29 | 7 | 87 | 56 |
| 10~14 | 12 | 40 | 8 | 36 | 8 | 99 | 63 |
| 14~18 | 16 | 48 | 10 | 42 | 10 | 116 | 70 |
| 18~24 | 16 | 52 | 12 | 48 | 12 | 132 | 80 |
| 24~30 | 18 | 54 | 14 | 50 | 12 | 136 | 80 |
| 30~40 | 20 | 60 | 16 | 56 | 15 | 156 | 90 |
| 40~50 | 25 | 65 | 18 | 58 | 15 | 163 | 90 |
