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19 Mar, 2026
TP-Link Gigabit Single-Mode WDM Bi-Directional SFP Module
£12.89
£15.47 inc. VAT
Out of Stock(0)MPN: SM321A-2
🚚 Next-day delivery £4.95
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Key Features
TP-Link TL-SM321A-2 V1
SFP (mini-GBIC) transceiver module
1GbE
1000Base-BX
LC/UPC single-mode
up to 2 km
1310 (RX) / 1550 (TX) nm
Product Overview
AI-generated summary
If you need a cheap, reliable optical “reach extender” for an existing single‑mode fibre link, this TP‑Link single‑mode WDM bidirectional SFP is the kind of component that does the job without drama. At £12.89 ex‑VAT it’s strong value for budget-minded networking—especially for small sites, spare parts, or replacing like‑for‑like modules when a switch vendor’s branded SFPs are priced like they’re made of gold. In day-to-day use, the real win is simplicity: plug it in, match it with the correct WDM pair on the other end, and you’re back to stable connectivity.
That said, don’t treat it as “universal SFP magic.” The WDM part means wavelength pairing matters, and it must match what your other end expects—otherwise you’ll get connectivity issues or poor signal. Also, with SFPs like this, compatibility depends on your specific switch model/firmware—some gear is picky. If you’re adding to an existing link, it’s worth confirming the exact optical type you already have (or what the far-end module is) before buying. If you’re unsure, buy from the same ecosystem or at least verify compatibility first; if you get the pairing right, it’s a great low-cost buy.
Specifications
Performance
SFP transceiver typeFiber optic
Maximum data transfer rate1250 Mbit/s
Interface typeSFP
Single-mode fiber (SMF) supportedY
Multi-mode fiber (MMF) supportedN
Features
Product colourMetallic
Hot-swapY
Power
Input voltage3.3 V
Certificates
Compliance certificatesRoHS
CertificationCE, FCC
Operational conditions
Operating temperature (T-T)0 - 70 °C
Storage temperature (T-T)-40 - 80 °C
Operating relative humidity (H-H)10 - 90 %
Storage relative humidity (H-H)5 - 90 %
Packaging content
Quantity per pack1 pc(s)
Packaging data
Package width81.5 mm
Package depth122.5 mm
Package height38.5 mm
Package weight60 g
Logistics data
Harmonized System (HS) code85369010
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