Arista Networks QSFP-40G-LR4-20 Compatible 40G QSFP+ ELR4 Transceiver Module

Built for hosts recognizing QSFP-40G-LR4-20, this HT-manufactured QSFP+ module delivers 40G transmission at 1310nm. Its rated reach is 20km, with Duplex LC as the physical interface. The specifications and engineering guidance below support high-density deployments balance optical performance, port access and thermal planning, while keeping HT manufacture separate from the OEM cross-reference.
OEM Part Number: QSFP-40G-LR4-20HT Part Number: QSFP-ELR4-40G
Product Highlights
- Compatible alternative to Arista Networks QSFP-40G-LR4-20
- 40G connectivity at 41.2Gbps (4x 10.3Gbps)
- Optical wavelength: 1310nm
- Specified reach: 20km
- Duplex LC / SMF interface
- Operating temperature: 0 to 70°C(32 to 158°F)
- Factory compatibility verification and optical performance testing before shipment
Specifications
| Arista Networks Compatible | QSFP-40G-LR4-20 |
|---|---|
| Manufacturer | HT |
| HT Part Number | QSFP-ELR4-40G |
| Form Factor | QSFP+ |
| Max. Data Rate | 41.2Gbps (4x 10.3Gbps) |
| Wavelength | 1310nm |
| Max. Transmission Distance | 20km |
| Connector | Duplex LC |
| Media | SMF |
| Transimitter Type | DFB CWDM |
| Receiver Type | PIN |
| TX Power | -4.5~2.3dBm |
| Receiver Sensitivity | <-12.5dBm |
| Power Budget | 8dB |
| Receiver Overload | 3.3dBm |
| Max. Power Consumption | ≤3.5W |
| Extinction Ratio | >3.5dB |
| Operating Temperature | 0 to 70°C(32 to 158°F) |
| Protocols | QSFP+ MSA, SFF-8436 |
Applications and Optical Link Design
Use this module for equipment interconnection over the specified single-mode fiber plant, including enterprise backbone, campus, metro or data-center interconnect links according to its rated distance. Confirm that both ends use the same optical standard and wavelength plan, and allow for connector, splice and patch-panel loss within the stated power budget.
Before deployment, check the host port type, supported data rate and firmware requirements. The 40G interface configuration must match the remote equipment; sharing a QSFP+ housing alone does not make two transceiver types interoperable.
Before commissioning, measure the complete single-mode channel against the stated budget for 20km. Inspect every Duplex LC connection and record diagnostic power where supported. Both ends must agree on rate, wavelength and optical standard.
Quality Assurance and Packaging
Before packing, the module receives interface inspection, identification and link checks. Protective packaging avoids pressure on the connector and latch. Customer references, rack groups and project packing lists can be added for volume orders.
Optical Acceptance, Diagnostics and Handling
For this model, the specified transmit-power range is -4.5~2.3dBm; receiver sensitivity is <-12.5dBm; the stated optical power budget is 8dB. Digital diagnostics make later maintenance easier when baseline values are captured at installation. Save the initial readings with the port and OEM reference, then investigate meaningful changes rather than reacting to a single transient value. Diagnostic support depends on the host as well as the module, so unavailable fields should be confirmed with the platform documentation. Before every insertion, keep dust caps in place until the patch lead is ready, avoid touching the optical end face and use an appropriate inspection and cleaning procedure. Do not look into an active optical interface.
High-Density Port and Thermal Planning
In a densely populated chassis, connector access and airflow form part of the optical-link design. Confirm that neighboring modules and patch leads leave room for latch operation, and include listed power consumption in the host thermal budget. Assess port density together with fiber management. For this model, the principal parameters are data rate 41.2Gbps (4x 10.3Gbps), wavelength 1310nm, rated reach 20km.
Ordering Information
Use QSFP-40G-LR4-20 as the compatibility cross-reference and QSFP-ELR4-40G as the HT ordering identity. Keep other reaches or wavelength directions on separate order lines. Neutral labels, customer packaging and project-specific compatibility review are available on request.
Arista Networks Compatibility and Factory Testing
The module is checked for host recognition as QSFP-40G-LR4-20, link establishment and diagnostic reporting. Physical cage fit alone is not treated as evidence of compatibility. Equipment model, hardware revision and software release can be reviewed before dispatch where platform behavior is uncertain.
Frequently Asked Questions
Is this an original Arista Networks transceiver?
No. It is an HT-manufactured compatible alternative for equipment that specifies QSFP-40G-LR4-20, not an original Arista Networks-branded module.
Which fiber and connector are required?
Use Duplex LC with SMF. The specified maximum reach is 20km, subject to fiber quality and total link loss.
Can it be mixed with another wavelength or reach version?
Only when the two ends share the same optical standard, wavelength plan and supported data rate. Check the exact part numbers and link budget rather than relying only on the module form factor.
Shipping and Lead Time
Standard configurations normally ship within one to three working days, with production lead times confirmed for larger quantities. International courier, air freight and sea freight are available; customer courier accounts and nominated forwarders are accepted.
10/100BASE-T SFP