ST-ST adapter: A passive device used to connect two ST-type fiber optic connectors to ensure that the cores of the two optical fibers are precisely aligned to achieve low-loss transmission of optical signals.

FC-FC adapter: A passive device designed for FC-type optical fiber connectors. It connects two FC connectors through a precise thread locking mechanism to achieve stable docking of single-mode and multimode optical fibers. It has low loss and high durability, and is suitable for long-distance and high-reliability communication scenarios.

ST-FC fiber coupler, also known as ST-FC fiber adapter and ST-FC fiber flange, is an important component used to connect two different types of fiber connectors, ST interface and FC interface. It can realize the conversion between different interfaces, make the optical path unblocked, and allow the light energy output by the transmitting optical fiber to be coupled to the receiving optical fiber to the maximum extent. Its ST interface is a keyed snap-on locking structure with a round buckle to ensure accurate alignment during connection; the FC interface adopts a metal sleeve for external reinforcement and a screw buckle for fastening. The coupler has the advantages of simple operation, stability and reliability, long life, easy maintenance and low price. It is widely used in optical fiber distribution frames (ODF), optical fiber communication equipment, instruments, telecommunication long-distance optical transmission networks, optical fiber access networks, data communication networks, local area networks (LANs), optical fiber CATV and other fields.

The SMA905 adapter is a right-angle (90-degree) RF adapter that belongs to the SMA (SubMiniature version A) connector family and is designed for vertical connection of coaxial cables or devices in space-constrained scenarios. Its core function is to convert signal direction to avoid signal loss or mechanical damage caused by cable bending.