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Tests USOC and EIA/TIA T568A/B cabling.

Price: $157.55

Extended Double Diamond™ Warranty Available (3 Additional Year)

Product Features

  • LEDs alert you to shorts, opens, reversals, and miswires at a glance.
  • Built-in modular jacks for three different cabling systems—no need for adapters.
  • Accurately verifies the integrity of 2-, 3-, and 4-pair voice and data channels.
  • Details

    The Single-Line Tester's LEDs immediately alert you to shorts, opens, reversals and miswires at a glance. Simply snap and lock the master and remote together when not in use. The lightweight, rugged, and impact-resistant unit comes with a 9-volt alkaline battery.

    Tech Specs

    Connectors Master unit: (3) RJ-45;
    Remote unit: (3) RJ-45
    Indicators Master unit: (4) LEDs;
    Remote unit: (8) LEDs
    Power (1) 9-V alkaline battery (included)
    Size 1.6"H x 2.3"W x 5.5"D (4.1 x 5.8 x 14 cm)
    Weight 0.5 lb. (0.2 kg)
    NOTE: This device is designed strictly to test continuity and should never be inserted into a live circuit.

    NOTE: 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 Extended Double Diamond™ Warranty Available (3 Additional Year) 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.

    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.