We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in

Finisar Corporation

Finisar FTL4C1QL1L 40G QSFP+ 40GBase-LR4 10km LC SFP transceiver

SKU CH-QRS7-QKWBZ

Transmits 40 Gbps over single-mode fibre up to 10 km using 1310 nm wavelength and LC connectors with digital optical monitoring

  • Network Management TypeManaged
  • Uplink InterfaceSFP
  • 40 Gbps throughput for high-density links
  • 10 km reach over single-mode fibre
  • 1310 nm wavelength for reliable long-range transmission
  • LC duplex connector for standard patching
  • Digital optical monitoring enables real-time diagnostics

40G QSFP+ LR4 Transceiver

This Finisar FTL4C1QL1L module delivers 40Gbps connectivity over single-mode fibre using the 40GBase-LR4 standard. It is built for network operators and data-centre engineers who need managed 40G uplinks with LC duplex patching. The transceiver plugs into any QSFP+ port that accepts LR4 optics.

Reach limited to 10km on SMF

The LR4 specification supports links up to 10km over OS2 single-mode fibre at a 1310nm wavelength. Digital optical monitoring is included so administrators can track live power and temperature readings. Beyond 10km the optical budget is exhausted and errors will rise sharply.

LC duplex connector required

The module presents a standard LC duplex interface; patch cords and bulkhead adapters must match this connector type. If your patch panels use MPO or SC terminations you will need hybrid cables or adapter panels. No other connector is compatible with this transceiver.

Highlights

  • 40 Gbps throughput for high-density links
  • 10 km reach over single-mode fibre
  • 1310 nm wavelength for reliable long-range transmission
  • LC duplex connector for standard patching
  • Digital optical monitoring enables real-time diagnostics

Specifications

BrandFinisar
Part NumberFTL4C1QL1L
Network Management TypeManaged
Uplink InterfaceSFP

Questions about this item

Should I pick the 40G QSFP+ LR4 version or a shorter-reach alternative?

Choose the 40GBase-LR4 module when your single-mode fibre run reaches up to 10 km; shorter-reach SR4 or eSR4 types only cover a few hundred metres.

What does the 40 Gbps rating mean once the transceiver is installed in a switch?

The module delivers four 10 Gbps lanes that aggregate to 40 Gbps line rate, so a 40G QSFP+ port sees full wire-speed throughput without oversubscription.

Is the LC single-mode interface limited to 2 km or can it reach 10 km?

The LC single-mode interface on this LR4 module is specified for 10 km at 1310 nm; the 2 km figure applies to a different LR variant, not this part.

Also in this aisle

People compared these

Same shelf, same checkout — eight coins and a 30-minute rate lock.