USR Courier®56K* V.92 Business Modem - Discontinued

NOTE: The USR843453C has been discontinued. The Courier Lite 56K Business Modem (USR845686G-PRO) is the recommended replacement‡. The USR845686G-PRO does NOT support leased-line connections, Synchronous, or V.25 bis.

Overview & Features     Specifications    Feature spotlight     Data Sheet     Support

Specifications & Standards

  • ITU V.92/V.90 up to 56 Kbps downloads
  • Data: V.92, V.90, V.34, V.32bis, V.32, V.22bis, V.22, V.23, and V.21
  • ITU V.34 at 33.6 Kbps or 28.8 Kbps
  • V.32 at 19.2 Kbps (21.6 Kbps between Courier modems with ASL)
  • ITU V.32bis at 14.4 Kbps
  • HST at 16.8 Kbps
  • Compatible with most ITU and Bell standards down to 300 bps
  • Data Error Control; Compression: V.42/V.42bis and MNP2-4/5
  • Fax: ITU V.17 at 14.4 Kbps, ITU V.29 at 9600 bps, ITU V.27ter at 7200 bps, Group III, TIA/EIA 578 Class 1, and TIA/EIA 592 Class 2.0
  • Caller ID and distinctive ring (require service from your local phone company/Caller ID may not be supported in some countries)
  • Hayes Compatible


  • Temperature: Operating Temperature conditions: 0 to 50 degrees C, Non-Operating Temperature conditions: -20 to 70 degrees C
  • Humidity: Operating Humidity conditions: 20% to 80% non-condensing, Non-Operating Humidity conditions: 5% to 95% non-condensing


  • FCC approved (Part 15/Part 68)
  • IC approved (ICES-003/CS-03)
  • UL/CUL listed
  • CE approved (Class B)
  • ROHS Compliant
  • REACH Compliant

Package Dimensions/Weight

  • 11.25 x 4.5 x 7.0 in. (28.58 x 11.43 x 17.78 cm)
  • 3.4 lb (1.54 kg)

Product Dimensions/Weight

  • 5.1 x 10.2 x 1.2 in. (13 x 26 x 3 cm)
  • 1.1 lb (0.5 kg)

Minimum Systems Requirements


  • Supports all major operating systems: DOS, Windows 3.1/95/98/Me/NT 4.0/2000/2003/2003 64 bit/XP/XP 64 bit/Vista/Vista 64 bit/Server 2008/Win 7/Win 7 64 bit/Win 8/Win 8 64 bit/Server 2011/Server 2012/Win 10/Win 10 64 bit/Server 2012 R2/Server 2016/Server 2019, UNIX, Linux, and any operating system that supports an RS-232 serial port (Unimodem TSP/TAPI compliant)
  • Available RS-232 serial port
  • 56K compatible local analog phone line

Software (ICN/Instant Update)

  • IBM compatible PC with 486DX or Pentium processor or equivalent
  • Internet Call Notification (ICN) supports Windows 95/98/Me/2000/XP


  • V.90 requires a V.90 56K ITU standard capable service provider
  • V.92 requires a V.92 56K ITU standard capable service provider
  • V.92 Call Notification feature requires Call Waiting service from your local phone company
  • V.92 Call Identification feature requires Call Waiting/Caller ID services from your local phone company

Package Contents

  • USRobotics Courier 56K Business Modem
  • RJ-11 phone cord (7 ft/2.13 m)
  • VersaPower Kit (Universal power adapter 100 V – 240 V) with UK, European, China and US plugs (6 ft/1.8 m)
  • UK, French, German and Italian Phone Adapters
  • Telephone line filter
  • RS-232 serial cable (3 ft/0.91 m)
  • Installation CD-ROM
    • Quick Reference Card
    • User Guide


Limited lifetime manufacturer warranty from date of purchase. Click here for full warranty information.

** Support for 64 bit operating systems requires a driver update (available in the support section of this website).
* Capable of receiving at up to 56 Kbps and sending at up to 48 Kbps (or 31.2 Kbps with V.90 server). Due to FCC regulations on power output, receiving speeds are limited to 53.3 Kbps. Actual speeds may vary. V.92 and V.90 features require compatible phone service and support from your Internet Service Provider (ISP). USRobotics modems featuring V.92 enhancements are backward compatible and will negotiate the highest possible speed when connecting to an ISP.
† Requires Windows operating system.

‡ Courier Lite (USR845686G-PRO) is the recommended replacement for Courier USR843453C, but features and specifications do vary. It is suggested to verify requirements before purchasing replacement units.


Courier®56K* V.92 Business Modem


Recommended Replacement‡: USR845686G-PRO

MSRP £ ex Vat:

Product Code : USR843453C
(Replaces USR013453C)

Approved for EU , Israel, South Africa, Pakistan

Additional Availability

US & Canada - Discontinued
Asia Pacific- Discontinued

Global Country Approvals & Accessory Kit Guide
Approved for use in over 75 countries*!

Additional Power Supply

110-240 V for US, UK and Europe
3453C Power Supply

* Kit may be required.

Contact Us

  • Phone (UK):
    0808 234 5935
  • Phone (Ireland):
    +44 (0)808 234 5935

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