TRENDnet
TRENDnet USB to Serial 9-Pin Converter Cable, TU-S9
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*Price sourced from Amazon.com. Last updated 2026-08-25. Price and availability subject to change.
Bottom line: The TRENDnet USB to Serial 9-Pin Converter Cable, TU-S9 is a niche pick — read recent reviews before buying in the cables & connectors category, priced around $10.99. Compare close alternatives before committing.
The TRENDnet TU-S9 USB to Serial 9-Pin Converter Cable bridges the gap between a modern laptop and the RS-232 gear that refuses to retire. If your desktop dropped its DB9 header years ago but you still need to reach a modem, a managed network switch, a console port, or a serial printer, this adapter puts a standard RS-232 9-pin connector on the end of a USB Type A plug. It runs at a 6Mbps data rate, supports USB 1.1, and works in USB 2.0 and USB 3.0 ports, so you are not hunting for a specific port on the machine. The integrated cable measures 540mm (21 in.), with a 25-inch total length…
SpecPicks Verdict
SpecPicks scored TRENDnet USB to Serial 9-Pin Converter Cable, TU-S9 using a rating × review-volume × price-fit model applied to our editorial and benchmark analysis across the cables & connectors category. TRENDnet's cables & connectors lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Mixed or limited buyer feedback at this price point — focus your evaluation on recent reviews that specifically address build quality and long-term reliability, and shortlist one or two close alternatives before deciding.
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
| 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 |
|---|---|
| Brand | TRENDnet |
| Color | White |
| Finish | White |
| EASY SETUP | Simple installation in seconds of the USB to Serial 9-Pin Converter Cable. Insert the your computer |
| Unit Count | 1 Count |
| Connectivity | USB |
| Model Number | TU-S9 |
| Compatibility | Mac |
| Input Voltage | 5 volts_of_direct_current |
| Nominal Power | 2.5 watts |
| Built-In Media | CD-ROM (Driver and User’s Guide), Quick Installation Guide, TU-S9 |
| Connector Type | USB Type A |
| Item Dimensions | 2.56 x 1.38 x 0.39 inches |
| Mfr Part Number | TU-S9 |
| Number of Items | 1 |
| Number of Ports | 3 |
| Power Plug Type | No Plug |
| Compatible Devices | Gateways, Laptop, Modems, PLC controllers, POS systems, Printer |
| Warranty Description | 2 year |
Ready to buy?
TRENDnet USB to Serial 9-Pin Converter Cable, TU-S9 is sold on the used and vintage market, where eBay carries the live inventory — Amazon does not stock this part. Prices and condition vary by seller and move in real time, so we link the live listing rather than quote a cached price. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-08-25. Price and availability subject to change.
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