Fiber Connector Types: Which Uses a Twist-On Connection?
Short answer
A ST uses a bayonet push-and-twist lock, making it the fiber connector that matches the twist-on requirement rather than SC, LC or MPO.
Question
Key Takeaways
It tests fiber connector mating mechanisms, and the main trap is confusing ST’s bayonet twist-lock with SC’s push-pull latch or LC’s small-form-factor latch.
This N10-009 fiber connector question tests the difference between ST’s bayonet twist-lock and the push-pull or latch designs of SC, LC and MPO. The correct answer is A (ST), the Straight Tip connector.
Common mistake: Choosing B (SC) because it is a common fiber connector with a secure latch; SC is push-pull, not twist-on, so it fails the bayonet mechanism named in the question.
Expert Analysis
Why B (SC) is the tempting wrong answer B (SC) is the option most likely to attract a candidate who knows SC is a common fiber connector with a secure latch. The word “twist” can be mentally blurred with “lock,” and SC’s square body and audible click make it feel like the “secure” choice. It satisfies the general idea that fiber connectors must be locked into place, but it fails the specific action in the stem: SC is a push-pull connector. There is no bayonet rotation in the mating step.
The connector that actually twists A (ST), Straight Tip, uses a bayonet-style coupling: push the connector onto the adapter and twist to lock it. The supplied comment describes exactly this “push-and-twist (or twist-on/twist-lock) mechanism,” which is the discriminator the question is testing. ST is older, often ceramic or metal, and still appears in legacy multimode and some industrial fiber plants.
Why C and D do not fit either C (LC) is a small-form-factor connector with a latch, common in high-density patch panels; it clips rather than twists. D (MPO) is a multi-fiber push-on connector used for parallel optics and backbone trunks; its name even says push-on. Neither has a twist-on coupling.
Exam takeaway Treat connector questions as physical-mechanism questions. Match the verb in the stem to the mating action: ST = bayonet twist, SC = push-pull, LC = latch, MPO = multi-fiber push-on. That makes A the only answer.
Official Reference
https://www.comptia.org/certifications/network
This link opens the official vendor documentation in a new tab.
Exam Strategy
When a fiber connector question names a locking action, map it to the physical mating style before thinking about connector popularity or form factor. Say the mechanism aloud: bayonet push-and-twist is ST; push-pull square latch is SC; small-form-factor latch is LC; multi-fiber push-on is MPO. Eliminate any option whose lock is a latch or push-pull rather than a twist. This transfers to cabling questions that describe a physical action instead of a standard name.
Frequently Asked Questions
Why is SC not the twist-on fiber connector?
What physical mechanism identifies an ST connector?
Discussion 1 contributions
Compiled from public community threads and reader submissions, lightly edited for clarity. Handles and vote tallies are shown as recorded, and comments reflect the views of individual contributors.
From public community threads 1
-
ERB14 👍 1 Answered AA. ST (Straight Tip): This fiber-optic connector uses a bayonet-style mount with a push-and-twist (or twist-on/twist-lock) mechanism to secure the connection.
Reader comments & corrections
No reader corrections yet — spotted an error or have a note? Share it below.
Related Analysis
Practice All N10-009 Questions
Access 100 questions with complete answers and detailed explanations.
View Full N10-009 Practice Test →