| AS568 No. | Nominal Reference | Actual Dimensions | |||
| I.D. | O.D. | Width | I.D. Tolerance | Width Tolerance | |
| -241 | 3 7/8 | 4 1/8 | 1/8 | 3.859 ± .028 | .139 ± .004 |
| -242 | 4 | 4 1/4 | 1/8 | 3.984 ± .028 | .139 ± .004 |
| -243 | 4 1/8 | 4 3/8 | 1/8 | 4.109 ± .028 | .139 ± .004 |
| -244 | 4 1/4 | 4 1/2 | 1/8 | 4.234 ± .030 | .139 ± .004 |
| -245 | 4 3/8 | 4 5/8 | 1/8 | 4.359 ± .030 | .139 ± .004 |
| -246 | 4 1/2 | 4 3/4 | 1/8 | 4.484 ± .030 | .139 ± .004 |
| -247 | 4 5/8 | 4 7/8 | 1/8 | 4.609 ± .030 | .139 ± .004 |
| -248 | 4 3/4 | 5 | 1/8 | 4.734 ± .030 | .139 ± .004 |
| -249 | 4 7/8 | 5 1/8 | 1/8 | 4.859 ± .035 | .139 ± .004 |
| -250 | 5 | 5 1/4 | 1/8 | 4.984 ± .035 | .139 ± .004 |
| -251 | 5 1/8 | 5 3/8 | 1/8 | 5.109 ± .035 | .139 ± .004 |
| -252 | 5 1/4 | 5 1/2 | 1/8 | 5.234 ± .035 | .139 ± .004 |
| -253 | 5 3/8 | 5 5/8 | 1/8 | 5.359 ± .035 | .139 ± .004 |
| -254 | 5 1/2 | 5 3/4 | 1/8 | 5.484 ± .035 | .139 ± .004 |
| -255 | 5 5/8 | 5 7/8 | 1/8 | 5.609 ± .035 | .139 ± .004 |
| -256 | 5 3/4 | 6 | 1/8 | 5.734 ± .035 | .139 ± .004 |
| -257 | 5 7/8 | 6 1/8 | 1/8 | 5.859 ± .035 | .139 ± .004 |
| -258 | 6 | 6 1/4 | 1/8 | 5.984 ± .035 | .139 ± .004 |
| -259 | 6 1/4 | 6 1/2 | 1/8 | 6.234 ± .040 | .139 ± .004 |
| -260 | 6 1/2 | 6 3/4 | 1/8 | 6.484 ± .040 | .139 ± .004 |
| -261 | 6 3/4 | 7 | 1/8 | 6.734 ± .040 | .139 ± .004 |
| -262 | 7 | 7 1/4 | 1/8 | 6.984 ± .040 | .139 ± .004 |
| -263 | 7 1/4 | 7 1/2 | 1/8 | 7.234 ± .045 | .139 ± .004 |
| -264 | 7 1/2 | 7 3/4 | 1/8 | 7.484 ± .045 | .139 ± .004 |
| -265 | 7 3/4 | 8 | 1/8 | 7.734 ± .045 | .139 ± .004 |
| -266 | 8 | 8 1/4 | 1/8 | 7.984 ± .045 | .139 ± .004 |
| -267 | 8 1/4 | 8 1/2 | 1/8 | 8.234 ± .050 | .139 ± .004 |
| -268 | 8 1/2 | 8 3/4 | 1/8 | 8.484 ± .050 | .139 ± .004 |
| -269 | 8 3/4 | 9 | 1/8 | 8.734 ± .050 | .139 ± .004 |
| -270 | 9 | 9 1/4 | 1/8 | 8.984 ± .050 | .139 ± .004 |
| -271 | 9 1/4 | 9 1/2 | 1/8 | 9.234 ± .055 | .139 ± .004 |
| -272 | 9 1/2 | 9 3/4 | 1/8 | 9.484 ± .055 | .139 ± .004 |
| -273 | 9 3/4 | 10 | 1/8 | 9.734 ± .055 | .139 ± .004 |
| -274 | 10 | 10 1/4 | 1/8 | 9.984 ± .055 | .139 ± .004 |
| -275 | 10 1/2 | 10 3/4 | 1/8 | 10.484 ± .055 | .139 ± .004 |
| -276 | 11 | 11 1/4 | 1/8 | 10.984 ± .065 | .139 ± .004 |
| -277 | 11 1/2 | 11 3/4 | 1/8 | 11.484 ± .065 | .139 ± .004 |
| -278 | 12 | 12 1/4 | 1/8 | 11.984 ± .065 | .139 ± .004 |
| -279 | 13 | 13 1/4 | 1/8 | 12.984 ± .065 | .139 ± .004 |
| -280 | 14 | 14 1/4 | 1/8 | 13.984 ± .065 | .139 ± .004 |
| -281 | 15 | 15 1/4 | 1/8 | 14.984 ± .065 | .139 ± .004 |
| -282 | 16 | 16 1/4 | 1/8 | 15.955 ± .075 | .139 ± .004 |
| -283 | 17 | 17 1/4 | 1/8 | 16.955 ± .080 | .139 ± .004 |
| -284 | 18 | 18 1/4 | 1/8 | 17.955 ± .085 | .139 ± .004 |