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TRENDnet USB to Serial 9-Pin Converter Cable, TU-S9, USB to RS232 Serial Adapter, Supports Windows & Mac, 64cm (25 in.) Cable Length, NDAA Compliant, Plug & Play, White
TRENDnet

USB to Serial 9-Pin Converter Cable, TU-S9, USB to RS232 Serial Adapter, Supports Windows & Mac, 64cm (25 in.) Cable Length, NDAA Compliant, Plug & Play, White

By SpecPicks Editorial · Verified 2026-07-10

$12.99
Buy on Amazon — $12.99 Compare to similar cables & connectors

*Price sourced from Amazon.com. Last updated 2026-07-10. Price and availability subject to change.

Bottom line: The USB to Serial 9-Pin Converter Cable, TU-S9, USB to RS232 Serial Adapter, Supports Windows & Mac, 64cm (25 in.) Cable Length, NDAA Compliant, Plug & Play, White is a niche pick — read recent reviews before buying in the cables & connectors category, priced around $12.99. Read recent reviews carefully before committing.

This USB to Serial converter allows you to connect an RS-232 serial device such as a modem to a USB port on your desktop or laptop. USBSupports USB 1.1 and compatible with USB 2.0 and USB 3.0 ports.RS-232 Serial ConnectorConnect RS-232 serial devices such as modems and network switches using the widely supported USB standard found in most laptops and desktops today.Flexible CableIntegrated flexible 540 mm (21 in.) USB cable accommodates most installation scenarios. PACKAGE CONTENTS• TU-S9• Quick Installation Guide• CD-ROM (Drivers)

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SpecPicks Verdict

SpecPicks classifies TRENDnet USB to Serial 9-Pin Converter Cable, TU-S9, USB to RS232… as a niche pick — read recent reviews before buying in the cables & connectors category, based on our editorial and benchmark analysis and our ranking model that weights rating × review-volume × price-fit. TRENDnet's positioning sits within the broader category mid-tier. Use the Compare tool to put it side-by-side with two or three close alternatives before clicking through to Amazon.

Common buyer scenarios for cables & connectors of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the Amazon listing before purchase. Prices, stock, and Prime eligibility update directly from Amazon's catalog and may have moved since this page was last verified.

Pros & Cons

Pros

  • ✓ Backed by TRENDnet's warranty and support channels
  • ✓ Ships via Amazon with Prime eligibility and the standard returns policy

Cons

  • ✗ Confirm socket / form-factor / power-rating compatibility against your build before ordering
  • ✗ Price, stock, and Prime eligibility update from Amazon and may have changed since this page was last verified

Key Features

  • USB: The USB to serial adapter supports USB 1.1 and it is compatible with USB 2.0 and USB 3.0 ports with a 6Mbps Data Rate
  • NDAA COMPLIANT: With our NDAA compliant USB to Serial 9-Pin Converter Cable, you can plan and install networking solutions that Government customers demand today (U.S. and Canada Only)
  • MANUFACTURER PROTECTION: We stand by the quality of our products.The TU-S9 USB to Serial 9-Pin Converter Cable is backed and supported with 2 years of TRENDnet Manufacturer Protection.
  • RELIABLE TECH SUPPORT: Our team of advisors, support and tech experts are English speaking, and available for all your needs during normal business hours. We take pride in being there for our customers.
  • RS-232 SERIAL CONNECTOR: Connect RS-232 serial devices, such as modems or printers, using the widely supported USB standard found in most laptops and desktops today.
  • SUPPORTED OPERATING SYSTEMS: The USB to serial converter adapter is compatible with Windows and Mac operating systems. Windows 10, 8.1, 8, 7. Mac OS 10.11, 10.10, 10.9, 10.8, 10.7, 10.6

Full Specifications

USBThe USB to serial adapter supports USB 1.1 and it is compatible with USB 2.0 and USB 3.0 ports with a 6Mbps Data Rate
BrandTRENDnet
ColorWhite
FinishWhite
EASY SETUPSimple installation in seconds of the USB to Serial 9-Pin Converter Cable. Insert the your computer
Unit Count1 Count
ConnectivityUSB
Model NumberTU-S9
CompatibilityMac
Input Voltage5 Volts (DC)
Nominal Power2.5 Watts
Built-In MediaCD-ROM (Driver and User’s Guide), Quick Installation Guide, TU-S9
Connector TypeUSB Type A
Item Dimensions2.56 x 1.38 x 0.39 inches

Ready to buy?

TRENDnet USB to Serial 9-Pin Converter Cable, TU-S9, USB to RS232 Serial Adapter, Supports Windows & Mac, 64cm (25 in.) Cable Length, NDAA Compliant, Plug & Play, White is available on Amazon with Prime shipping and the full Amazon returns policy. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.

Check price on Amazon →

*Price sourced from Amazon.com. Last updated 2026-07-10. Price and availability subject to change.

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TRENDnet USB to Serial 9-Pin Converter Cable, TU-S9, USB to RS232 Serial Adapter, Supports Windows & Mac, 64cm (25 in.) Cable Length, NDAA Compliant, Plug & Play, White
$12.99
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