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Fiber Optic Inline Attenuator Single Mode LC/PC 20 DB

Connect to your LC/PC fiber connectors to buffer overpowering fiber signals.


30 In Stock
Same Day Shipping (before 5PM ET)
Lifetime Double Diamond™ Warranty (Standard)

*Required field

Product Features

  • High-precision doping technology for low back reflection and increased fiber signal accuracy.
  • Ideal for use in CATV, LAN, WAN, and telecommunications applications.
  • Precision zirconia alignment sleeve.


  • Guaranteed return loss of -55 dB.
  • Protect equipment from being overpowered.
  • Choose from five fixed attenuation values.

  • Use these attenuators with single-mode cable to filter the strength of the fiber optic signal.

    Fiber equipment located too close to other fiber equipment? Having problems with transmissions? Data being corrupted? Getting system failures? The problem is easier to fix than you may think.

    When a fiber device is very close to another one—for example, as little as 3 feet (0.9 m)—the signal is extremely strong. The light signal doesn't have time to attenuate or lose strength as it travels down the fiber. This is called receive saturation. The energy level of the fiber optic signal is too high and exceeds the operating range of the receiving equipment. So when the light reaches the other end, it reflects back along the cable. This reflection distorts the signal and disrupts data.

    Solve the problem with our attenuators. They feature guaranteed return-loss measures to attenuate the signal. To achieve the fixed return loss, the attenuators use a doped single-mode fiber with a wavelength of 1310–1550 nm.

    Use the attenuators in CATV, LAN, WAN, and telecommunications applications. When you have multiple fiber runs, use the attenuators to make sure all are operating at the same optical level. You can also use the attenuators as part of your test kits to verify optical levels.

    Tech Specs

    Attenuation 2, 5, 10, 15, or 20 dB
    Attenuation Tolerances 2 or 5 dB: ± 0.5 dB; 10, 15, or 20 dB: ± 1.0 dB
    Cable Type Single-mode fiber optic
    Connectors LC with PC contacts
    Return Loss -55 dB typicall
    Wavelength 1310/1550 nm

    * Technical specification weight is the unit weight. It is not the packaged shipping weight. For shipping weight, please contact Black Box customer service at 877-877-2269.



    Double Diamond Warranty Diamond

    Double Diamond™ Warranty (Standard)

    Take the risk out of equipment purchases with the Double Diamond™ Warranty from Black Box Network Services.

    The Double Diamond Warranty is our warranty that protects your Black Box® brand products* from accidental damage, including drops, water, and power surges.

    The Fiber Optic Inline Attenuator Single Mode LC/PC 20 DB comes with a standard Lifetime Double Diamond™ Warranty (Standard) already included.

    During the warranty period, Black Box Network Services will repair or replace your damaged equipment within one week of receipt at NO CHARGE!*

    Plus, get an Extended Double Diamond Warranty.

    You can also extend your warranty or protect a previously purchased Black Box® brand product** for an additional year—for only 10% of the purchase price! Or, extend your coverage for a full three years for only 20% of the purchase price!

    Ordering an extended warranty is easy: When viewing a product in your shopping cart, just select the one or three years of additional coverage in the dropdown menu under “Warranty Options.” For details, contact Customer Service at 724-746-5500.

    * Warranty subject to certain exclusions and limitations ** Certain products may not be eligible.

    What’s more, we also have a 45-day return policy. Simply call Customer Service for a Return Authorization (RA) number, return your product in new condition and in the original package, and receive a full refund.