HP 665243-B21 10Gb 2x 560FLR-SFP+ Adapter

Name: HP 665243-B21 10Gb 2x 560FLR-SFP+ Adapter
Brand: HP
SKU: 665243-B21

Dual-port 10Gb SFP+ FlexibleLOM adapter engineered to accelerate throughput in demanding HP ProLiant server environments.

$31.37*

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*Price sourced from Amazon.com. Last updated:Jul 14, 2026.Price and availability are subject to change.

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Overview

The HP 665243-B21 10Gb 2-Port 560FLR-SFP+ Adapter is a high-performance networking card designed for HP ProLiant servers equipped with FlexibleLOM slots. By using the dedicated FLR bay on the server motherboard, this adapter delivers dual 10Gbps SFP+ connectivity without consuming a standard PCIe expansion slot, leaving those slots available for storage controllers, GPUs, or other expansion cards. Each of the two ports supports full 10Gb line-rate throughput, and the adapter is optimized for low latency, making it an excellent choice for environments running heavy virtualization, iSCSI storage traffic, or latency-sensitive applications.

The 560FLR-SFP+ supports advanced features including SR-IOV for direct virtual machine access to network hardware, as well as multiple queue technologies that improve performance under VMware, Hyper-V, and Linux KVM hypervisors. The SFP+ interface provides flexibility in cabling, accepting both optical transceivers for longer runs and cost-effective direct-attach copper cables for short in-rack connections. For data center teams standardized on HP ProLiant infrastructure, this adapter offers a clean, integrated path to 10Gb networking with enterprise-grade reliability.

Specifications

Brand

Model

665243-B21

Product Type

Ethernet Adapter

Port Configuration

2-Port

Interface Type

560FLR-SFP+

Data Transfer Rate

10Gbps

Pros & Cons

👍 Pros

Dual 10Gb SFP+ ports provide high aggregate bandwidth from a single adapter
FlexibleLOM form factor frees up standard PCIe expansion slots for other cards
Low-latency design is well-suited for virtualization, storage traffic, and data-intensive applications
Supports SR-IOV for efficient virtual machine network I/O

👎 Cons

Requires a compatible HP ProLiant server with a FlexibleLOM slot, limiting use in non-HP hardware
SFP+ transceivers or DAC cables must be purchased separately
Only supports up to 10Gb speeds, not the newer 25Gb or higher standards
Firmware and driver support may vary depending on the server generation and operating system

Frequently Asked Questions

What server form factor does this adapter require?

The 560FLR-SFP+ is a FlexibleLOM (FLR) adapter, meaning it installs in the dedicated FLR slot found in compatible HP ProLiant Gen8 and Gen9 rack servers rather than a standard PCIe slot.

What type of transceivers or cables does this adapter use?

It uses SFP+ ports, which accept standard SFP+ transceivers or direct-attach copper (DAC) cables for 10Gb connectivity.

Does this adapter support both ports running simultaneously at 10Gbps?

Yes, both SFP+ ports can operate concurrently, each delivering up to 10Gbps of bandwidth.

Is this adapter suitable for virtualized server environments?

Yes, it supports features like SR-IOV and VMware NetQueue, making it well-suited for virtualized and high-density workloads.