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100KM Visual Fault Locator for Fiber Optic Cables, High-Power VFL Tester with FC/ST/SC/LC Support, Long-Range Fault Finder & Light Pen Tool for FTTH, Telecom, Datacenters, OTDR, Industrial Networks

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Availability: In Stock.
Fulfilled by Amazon

Arrives Sunday, Oct 26
Order within 23 hours and 29 minutes
Available payment plans shown during checkout

Size: 100KM VFL + FC/LC Connector


Color: Beryl


Number of Items: 1


Features

  • Pinpoint Faults with Visual Signal Tracing: The VFL emits a visible light signal that makes it easy to detect breaks, bends, and poor connections by highlighting irregularities along the fiber. Ideal for both new installations and routine maintenance, the light refracts at the fault location, making it highly visible in low-light environments or dense cabling setups.
  • Optimised for Field Use and Long Sessions: Designed with the needs of on-site technicians in mind, this device supports both pulse and continuous output modes. It features a consistent power level, extended battery life, and low-battery alert all powered by two AA batteries. Perfect for daily use in demanding network environments.
  • One Tool, Multiple Interfaces: Equipped with a 2.5mm universal interface, this VFL is compatible with ST, SC, FC, and LC connectors of both circular and square types. Its broad compatibility makes it a go-to tool for telecom engineers, fiber researchers, CATV technicians, and data infrastructure specialists.
  • Consistent Signal, Extended Reach: With high-efficiency internal circuitry, the VFL delivers stable signal output across fiber lengths of up to 100KM. Whether used in metro-area backbones, FTTH networks, or industrial automation setups, it enables quick fault isolation even across great distances.
  • Built to Withstand the Field: Encased in a durable aluminium alloy body with a stainless steel tip, the unit resists dust, shock, and electrostatic interference. Lightweight and easy to carry, it comes with a storage pouch and lanyard, making it ideal for mobile use during inspections, repairs, or installations.

Description

100KM Fiber Optic Fault Locator – High-Precision Diagnostic Tool for Long- Range Cable Testing Enhance your fiber network diagnostics with this advanced 100KM Visual Fault Locator, built for technicians who demand performance, durability, and precision. Designed to streamline installation, inspection, and repair, this tool is ideal for a wide range of professional environments including telecom, datacenters, and industrial applications. Key Features: 1. Ultra-Long Detection Capability: Identify fiber breaks, microbends, and poor terminations across distances of up to 100 kilometers. The device emits a visible light output, revealing fault points through light dispersion, helping professionals quickly isolate disruptions along long cable runs. 2. Broad Connector Compatibility: Fitted with a universal 2.5mm port, this VFL works seamlessly with ST, SC, FC, and LC connectors (round and square). It supports both single-mode and multi-mode fiber types, making it ideal for complex infrastructure such as CATV, campus networks, and fiber-based control systems. 3. Rugged Field-Ready Design: Robust Build: Constructed with a hardened aluminium alloy housing and reinforced stainless steel head, the unit resists shocks, dust ingress, and static discharge. Portable Form Factor: Weighing only 165g with a pen-style design, it's compact enough for daily carry in pockets or tool pouches. Dual Operating Modes: Easily toggle between continuous and pulse modes to accommodate different inspection conditions. 4. Reliable Power System: Powered by two replaceable AA batteries (not included), the device features a high-efficiency circuit to maintain consistent brightness. Built-in low battery warning ensures uninterrupted workflow in the field. 5. Built to Perform in Harsh Conditions: With an operating temperature range from 0°C to 60°C and storage tolerance down to -20°C and up to 70°C, this locator maintains optimal functionality in demanding outdoor or industrial environments. Recommended Applications: Telecom Network Diagnostics: Identify disruptions in fiber-to-the-home (FTTH) and metro fiber systems. Datacenter Cabling Verification: Detect faults in dense patch panels and server rooms. Educational & Enterprise Networks: Maintain performance across large-scale distributed systems. Industrial Fiber Monitoring: Ensure stable connections in automation and sensor systems. Technical Specifications: Material: Aircraft-grade aluminium body Wavelength: 650nm ± 20nm Maximum Detection Distance: 100KM Interface: ST/SC/FC/LC (FC male to LC female adapter optional) Dimensions: 175 x 26 x 26mm Net Weight: 165g Power Supply: 2 × AA batteries (not included) Operating Temperature: 0°C to 60°C Storage Temperature: -20°C to 70°C Package Contents: 1 × Visual Fault Locator (VFL) Pen 1 × FC Male to LC Female Connector 1 × Carrying Pouch 1 × Lanyard 1 × User Manual Usage Notes: 1. Always remove batteries during extended storage to prevent corrosion and maintain conductivity. 2. Clean the fiber connector regularly for accurate signal output and optimal test results. This 100KM Visual Fault Locator delivers the long-range testing power and reliability required by modern fiber optic professionals. Whether in the lab or in the field, it's a critical addition to any technician's toolkit.

Brand: GESD


Power Source: Battery Powered


Style: Visual Fault Locator


Color: Beryl


Upper Temperature Rating: 60 Degrees Celsius


Package Dimensions ‏ : ‎ 7.72 x 2.87 x 1.34 inches; 4.16 ounces


Date First Available ‏ : ‎ March 26, 2025


Manufacturer ‏ : ‎ GESD


Best Sellers Rank: #11,593 in Industrial & Scientific (See Top 100 in Industrial & Scientific) #23 in Network & Cable Testers


#23 in Network & Cable Testers:


Customer Reviews: 4.4 4.4 out of 5 stars 821 ratings


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Oct 26

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Nice and bright.
Size: 30KM VFL Color: Black Number of Items: 1
Well made and works perfectly in broad daylight. I've used it mostly on singlemode fiber but it works fine on multimode too. The included batteries are pretty low quality, so I'd keep an eye on them. After leaving the VFL on for a couple of hours straight, the included batteries started to leak a clear fluid which I'm pretty certain is corrosive. I removed them, cleaned out the battery compartment, and installed some quality name-brand alkaline AAs. ... show more
Reviewed in the United States on January 5, 2020 by Kevin H. Patterson

  • Updated
Size: 30KM VFL Color: Black Number of Items: 1
When it worked it worked well. After 3 months it stopped working. I contacted GESD the manufacturer and told them that I tried new batteries and they sent me a message back and told me to replace batteries. ??? So now I will buy a different version of this. Very disappointed. Update:; Changed to 5 stars as the customer service was very good when I contacted them again. They sent me replacements next day and sent 2 of them. Wow! They are worth the effort. Buy from them without hesitation. ... show more
Reviewed in the United States on December 18, 2019 by Wayde weaver

  • Plenty of light for the long haul.
Size: 50KM VFL + FC/LC Connector Color: Silver Number of Items: 1
I work in several areas which require checking light, finding the Z end of jumpers and connections that are not documented. This light so far has worked very well. I also try not to drop it, that seems to be a leading problem with all VFL's. So far so good.
Reviewed in the United States on April 11, 2024 by M. Rose

  • Battery Compartment Check Needed: Quality Control Issue with Fiber Optic Visual Fault Locator
Size: 50KM VFL + FC/LC Connector Color: Silver Number of Items: 1
The media could not be loaded. The Fiber Optic Visual Fault Locator works great. However, after a few uses, the laser became weak, so I decided to replace the batteries. To my surprise, one of the batteries was leaking, and corrosion had already started. If you're purchasing this product, please check the battery compartment before first use to ensure there are no issues. This seems more like a quality control issue rather than a product defect. ... show more
Reviewed in the United States on February 25, 2025 by Angel

  • Bright
Size: 30KM VFL Color: Black Number of Items: 1
This works great for the price
Reviewed in the United States on June 14, 2025 by TheRealKG

  • Splicers Best VFL
Size: 30KM VFL Color: Black Number of Items: 1
I have dropped my VFL in a manhole, off a telephone pole and used it in the rain and it still works. Greay well built product.
Reviewed in the United States on May 20, 2025 by AmazonBuyer808

  • Durability is low, all else is good
Size: 100KM VFL + FC/LC Connector Color: Beryl Number of Items: 1
Worked great for the first 126 fibers. Now the fiber will not lineup correctly to get maximum light into the fiber. Durability is one star. Brightness is 5 star. Battery longevity is 5 star. Look and feel 5 star. Ease of use is 5 star. Weight is 5 star. Fix the durability issue and you will have a winning product. Ordered replacement ceramic sleeve to fix issue. ... show more
Reviewed in the United States on September 24, 2025 by sjmp65 sjmp65

  • This product works amazing.
Size: 50KM VFL + FC/LC Connector Color: Silver Number of Items: 1
I’m in telecommunications and fiber pathing is a very important part of my day and this tool makes it very easy to do so.
Reviewed in the United States on September 16, 2024 by Edward muesall

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