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Shop›USB Cables & Adapters›StarTech.com Dell EMC QSFP-40G-ESR4 Compatible QSFP+ Module - 40GBASE-SR4 - 40GbE Multimode Fiber MMF Optic Transceiver - 40GE Gigabit Ethernet QSFP+ - MPO 400m - 850nm - DDM
StarTech.com Dell EMC QSFP-40G-ESR4 Compatible QSFP+ Module - 40GBASE-SR4 - 40GbE Multimode Fiber MMF Optic Transceiver - 40GE Gigabit Ethernet QSFP+ - MPO 400m - 850nm - DDM
£37.80
£45.36 inc. VAT
Out of Stock(0)MPN: QSFP40GESR4E
🚚 Next-day delivery £4.95
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Key Features
StarTech.com Dell EMC QSFP-40G-ESR4 Compatible QSFP+ Module, 40GBASE-SR4, 40GbE Multimode Fiber MMF Optic Transceiver, 40GE Gigabit Ethernet QSFP+, MPO Connector, 400m, 850nm, DDM, 40Gbps
Lifetime Warranty (QSFP40GESR4E)
QSFP+ transceiver module (equivalent to: Dell EMC QSFP-40G-ESR4)
40GbE
40GBASE-SR4
MPO multi-mode
up to 400 m
850 nm
Product Overview
AI-generated summary
At ~£38 ex-VAT, this StarTech QSFP+ module is one of those “sensible if you’ve checked compatibility” buys. The big catch with SFP/QSFP optics isn’t performance on paper—it’s whether your switch/router will actually accept it and whether you’re comfortable with third‑party behavior (DDM support helps, but that’s not the same thing as perfect DOM compatibility in every vendor setup). If you’re running Dell EMC gear and you’ve already found these work in your exact model/firmware combination, this is a cost-effective way to light up 40GbE on multimode without paying Dell-brand pricing.
I’d recommend it for budget-conscious teams maintaining existing data centre/server networking where they just need more ports to work reliably (and they can validate optics before committing). It’s not the right choice if you need “plug in and forget it” on day one across a mixed fleet, or if you can’t easily test in your specific environment—optics are one of the few network components where small incompatibilities can turn into annoying downtime. Bottom line: good value **if** you can confirm it’s supported in your exact Dell EMC QSFP+ slot/module compatibility scenario; otherwise, I’d spend a bit more on optics you know your switch will accept first time.
Specifications
Performance
SFP transceiver typeFiber optic
Maximum data transfer rate40000 Mbit/s
Interface typeQSFP+
Multi-mode fiber (MMF) supportedY
Fiber optic connectorMPO
Features
Product colourSilver
Hot-swapY
Mean time between failures (MTBF)45017120 h
Brand compatibilityDell
Compatible productsQSFP-40G-ESR4
Certificates
Compliance certificatesRoHS
CertificationCE, FCC, UL, REACH
Weight & dimensions
Width58.4 mm
Depth13.9 mm
Height12.6 mm
Weight40 g
Packaging content
Quantity per pack1 pc(s)
Packaging data
Package width120 mm
Package depth205 mm
Package height350 mm
Package weight60 g
Logistics data
Master (outer) case width120 mm
Master (outer) case length205 mm
Harmonized System (HS) code85369010
Master (outer) case height350 mm
Products per master (outer) case0 pc(s)
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