Black Box
Black Box USB to RS232 Opto-Isolated Converter
Bottom line: The Black Box USB to RS232 Opto-Isolated Converter is a specs-and-price decision rather than a crowd-consensus one in the expansion cards category, priced around $212.99 on Amazon as of 2026-10-06. Check the specification table below against one or two close alternatives — on price and spec fit, not on star ratings.
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*Price sourced from Amazon.com. Last updated 2026-10-06. Price and availability subject to change.
Pros & Cons
Pros
- ✓ Connects an RS-232 device to a PC's USB port
- ✓ Backed by Black Box's warranty and support channels
Cons
- ✗ Confirm socket / form-factor / power-rating compatibility against your build before ordering
- ✗ Price, stock, shipping and returns are set by the retailer and may have changed since this page was last updated
Manufacturer description
This compact opto-isolator enables you to attach an RS-232 device to a USB port and gain isolation from voltage spikes and ground loops. It doesn't require PCI or ISA slots, or IRQs. Using an optional USB Type A - Type B cable, simply plug the opto-isolator into the USB port and Windows will configure the device as an additional COM port. Manufacturer: Black Box Corporation. Manufacturer Part Number: SP385A-R3. Brand Name: Black Box. Product Model: SP385A-R3. Product Name: USB to RS232 Opto-Isolated Converter. Packaged Quantity: 1. Product Type: Transceiver/Media Converter…
SpecPicks Verdict
SpecPicks scored Black Box USB to RS232 Opto-Isolated Converter using a rating × review-volume × price-fit model applied to published specs and reviews across the expansion cards category. Black Box's expansion cards lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.
Common buyer scenarios for expansion cards 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 retailer's listing before purchase. Prices and stock are set by the retailer and may have moved since this page was last updated.
Key Features
- Connects an RS-232 device to a PC's USB port
- Protect your computer and RS-232 devices from voltage spikes and ground loops
Full Specifications
| Brand | Black Box |
|---|---|
| Color | Multicolor |
| Finish | Black |
| Unit Count | 1.0 Count |
| Connectivity | USB |
| Model Number | SP385A-R3 |
| Compatibility | PC |
| Warranty Type | Limited |
| Connector Type | USB Type B |
| Item Dimensions | 6.1 x 5.9 x 2.5 inches |
| Mfr Part Number | SP385A-R3 |
| Number of Items | 1 |
| Number of Ports | 2 |
| Power Plug Type | No Plug |
| Compatible Devices | RS-232 Device |
| Warranty Description | No Warranty |
| Item dimensions L x W x H | 6.1 x 5.9 x 2.5 inches |
| Global Trade Identification Number | 00822088135289 |
Ready to buy?
Black Box USB to RS232 Opto-Isolated Converter is listed on Amazon. Price, availability, shipping and returns are set by Amazon and its sellers — check the listing for current terms. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-10-06. Price and availability subject to change.
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