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CSU/DSU MS DBU Base Unit, Base Unit

Re-establish your data link fast—get failsafe DDS backup.


Please call 877-877-2269 for a replacement product or part.

Product Features

  • Supports DDS rates from 2.4 to 64 kbps, including 19.2 and 38.4 kbps.
  • Embedded SNMP and Telnet™ via dedicated RS-232 control port.
  • Two slots available.


  • The optional V.34 Modem Backup module (MOV3298426) gives you dial backup to re-establish your data links faster than ever.
  • The modular design enables you to upgrade to ISDN without replacing the entire unit.

  • Tech Specs

    Interface DTE: Both EIA-232 and V.35 electrical and physical DTE interfaces; Line: RJ-48S, 4-wire, full-duplex
    Power 115 VAC, 60 Hz, 7 W
    Size 2.4"H x 8"W x 10.4"D (6.1 x 20.3 x 26.4 cm)
    Speed Sync: 2.4, 4.8, 9.6, 19.2, 38.4, 56, and 64 kbps; Async: 2.4, 4.8, 9.6, 19.2, 38.4, and 57.6 kbps
    Weight 4.5 lb. (2.0 kg)
    This product works with:
  • CSUDSU MS DBU Backup Modules (MOV3298426 or MT139C)
  • RS-232 Cable, 25-Conductor, Male/Male (ECM25C)
  • V.35 Interface Cable, Male/Male (EYN450-MM)
    Questions? Contact our free Tech Support.

    * 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.

  • Warranty

    Double Diamond Warranty

    Sold As is with no warranty.


    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.