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Multiport Modem Sharing Device, 2-Port

Share one device with up to eight terminals.


Please call 877-877-2269 for a replacement product or part.
Extended Double Diamond™ Warranty Available (3 Additional Year)

Product Features

  • Enables up to eight terminals to share one modem, multiplexor, or DDS circuit.
  • Supports sync data rates up to 38.4 kbps.


  • Works with dialup and leased-line modems.

  • Connect up to eight terminals to one modem or computer port with these Multiport Modem Sharing Devices. You can connect up to two devices with the 2-port version and up to eight devices with the 8-port version. They're compatible with dialup and leased-line modems.

    Each unit includes port enable/disable switches, activity indicators, master port DCE/DTE selection switch, and three clock options: master port, internal clock, or external from port 1. For systems with more than eight DTEs, cascade Multiple Modem Sharing Devices to provide access to a master-port device.

    Tech Specs

    Connectors 33821: (3) DB25 F; 32457: (9) DB25 F
    Dimensions 33821: 1.7"H x 10"W x 6.5"D (4.3 x 25.4 x 16.5 cm); 32457: 1.9"H x 12.8"W x 9.5"D (4.8 x 32.5 x 24.1 cm)
    Interface Subchannels: RS-232, DCE; Master Port: RS-232, DTE/DCE
    Line Type Point-to-point or multipoint
    Operation Half- or full-duplex
    Power 115 VAC, 60 Hz
    Speed Async: 33821: Up to 115.2 kbps; 32457: Up to 38.4 kbps; Sync: Internal: Up to 38.4 kbps; External: Up to 64 kbps

    * 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 1 Year Warranty Available

    Protect your purchase with an additional 1 Year Double Diamond™ warranty!
    Cost: $19.00

    Extended 3 Year Warranty Available

    Protect your purchase with an additional 3 Year Double Diamond™ warranty!
    Cost: $37.99


    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 Multiport Modem Sharing Device, 2-Port comes with a standard 1 YEAR warranty 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.