Which plastic fiber connector features a locking tab and is used for both single- and multi-mode cabling?

• A. MT-RJ Connector
• B. ST Connector
• C. SC Connector
• D. LC Connector

Answer: (A)

The key idea is how fiber connectors stay securely mated and what fiber types they support. The MT-RJ connector is designed as a duplex, two-fiber plug in a single rectangular ferrule, and it uses a locking tab on the connector housing to secure it in its receptacle. That locking tab provides a reliable retention mechanism, reducing the chance of accidental unplugging in active networks. Because MT-RJ was commonly deployed with both single-mode and multimode fiber in various installations, it’s associated with compatibility with both types of cabling.

Other connectors rely on different retention methods—some use bayonet twists, others push-pull latches, and still others have different locking mechanisms—so they don’t emphasize a locking tab in the same way or aren’t as universally described as supporting both fiber types in the same form factor. The locking tab feature and the duplex, two-fiber, single-rectangular-ferrule design are the distinguishing aspects that align with MT-RJ.