Choke Flanges (mil. std.)
| Waveguide | Aluminium alloy | Copper alloy | Shape* |
| WR 22 | | | |
| WR 28 | UG600A/UA | UG600A/U | CA |
| WR 34 | | / | CA |
| WR 42 | UG598A/U | UG596A/U | RO |
| WR 51 | | | |
| WR 62 | UG1666/U | UG541A/U | CA |
| WR 75 | | | |
| WR 90 | UG136B/U | UG40A/U | CA |
| WR 112 | UG137B/U | UG52B/U | CA |
| WR 137 | UG440B/U | UG343A/U | RO |
| WR 159 | | | |
| WR 187 | UG406B/U | UG148B/U | RO |
| WR 229 | / | / | |
| WR 284 | UG585A/U | UG54A/U | RO |
| WR 340 | UG554A/U | UG553A/U | RE |
| WR 430 | UG437B/U | UG435/U | RE |
| WR 510 | / | / | |
| WR 650 | UG418B/U | UG417B/U | RE |
*CA : square
RE : rectangular
RO : circular