What This Product Does
TP-Links TL-SM321B adopts the latest standard 1000Base-BX, transmitting over one single-mode fiber with one different wavelength going in each direction. Paired with TL-SM321A, You can extend the network distance up to 20Km with TP-Links routers, switches and media converters for reliable high-speed long-distance communication.

Up to 20 km transmission distance with 9/125 m SMF (Single-Mode Fiber)
Bidirectional WDM communication on a single fiber
Compatible with Small Form Pluggable Multi-Source Agreement (SFP-MSA)
Supports Digital Diagnostic Monitoring (DDM)
Hot-swappable module design
Work with TL-SM321A as a pair

What’s in the box:
TL-SM321B