1. Connector: A separable element (except an adapter) that is usually attached to a cable or device for electrical connection of a transmission line system.

2. RF connector: It is a connector used in the RF range.

3. Video: Radio waves with a frequency range between 3HZ∽30MHZ.

4. Radio frequency: radio waves with a frequency range of 3000HZ∽3000GHZ.

5. High frequency: Radio waves with a frequency range between 3MHZ∽30MHZ.

6. Coaxial: The inner conductor has a dielectric support, and the structure can obtain the minimum internal reflection coefficient within the frequency range used in the measurement.

7. Triax: A transmission line consisting of three layers of concentric conductors with a common axis and insulated from each other.

8. Grade: The level of the connector in terms of mechanical and electrical precision, especially in terms of the specified reflection coefficient.

9. Universal Connector (Class 2): A connector manufactured with the widest allowable dimensional deviation (tolerance), but still guaranteeing the minimum specified performance and intermateability.

Note: The requirements for reflection coefficient can be specified or not specified.

10. High-performance connector (Class 1): A connector that specifies the limit value of the reflection coefficient according to the frequency change. Usually, the specified dimensional tolerance is not stricter than the corresponding Class 2 connector, but it is necessary to ensure that the connector meets the reflection coefficient. It is the manufacturer's responsibility to select tighter tolerances when required.

11. Standard Test Connector (Class 0): A precision-manufactured specific type of connector used for reflection coefficient measurements on Class 1 and Class 2 connectors, with negligible errors in measurement results.

NOTE: Standard test connectors are usually part of different types of adapters, and adapters and precision connectors form part of the test equipment.

12. Seal

12.1 Sealed connector: a connector that can meet the specified gas, moisture or liquid tightness requirements.

12.2 Barrier seal: A seal that prevents gas, moisture or liquid from entering the interior of the connector housing along the axial direction.

12.3 Panel sealing: Prevent gas, moisture or liquid from entering the seal between the fixed or adapter housing and the panel through the mounting hole.

       NOTE: Seals are usually available as separate products.

12.4 Mating face seal: A seal at the interface that prevents gas, moisture or liquid from entering a pair of mating connectors.

12.5 Hermetic sealing: The sealing that meets the requirements of test Qk in IEC60068-2-17 "Basic Environmental Test Procedures Part 2: Test-Test Q: Sealing".