# Transceiver BlueOptics BO25K859S3D 40G-QSFP-ESR4 Copper 10000 Mbit/s SFP+

**URL:** https://aio.lv/en/product--blueoptics-40g-qsfp-esr4-bo--10621321
**Data updated:** 2026-02-25 16:39 (EET)
**Category:** Network Media Converters
**Manufacturer:** BlueOptics
**Manufacturer code:** 40G-QSFP-ESR4-BO
**EAN:** 4063232312279
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 119.49 €
**Prices and availability valid until:** 2026-08-28 23:59
**Price without VAT (21%):** 98.75 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--blueoptics-40g-qsfp-esr4-bo--10621321

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 27.08.2026 | free |
| Pickup points | 01.09.2026 | 1.79 EUR |
| Courier delivery to door | 01.09.2026 | 4.99 EUR |

## Summary description

The BlueOptics BO25K859S3D is a 40G-QSFP-ESR4 compatible transceiver designed for high-speed data transfer. It supports a maximum data rate of 10000 Mbit/s and features a copper interface type SFP+. This lightweight module weighs only 20 g and is compatible with Dell products, making it ideal for network expansions and upgrades.

## Long description

The BlueOptics BO25K859S3D 40G-QSFP-ESR4 Copper transceiver is a compact module designed for high-speed network environments. It supports up to 10000 Mbit/s and uses a copper SFP+ interface to provide a short-range, high-throughput connection. The module is lightweight and compatible with Dell hardware, intended for network expansions, server uplinks and switch interconnects where a reliable 10 Gigabit Ethernet link is required.
Advantages
This transceiver offers a compact form factor and a copper SFP+ interface that simplifies installation in existing 10 Gigabit Ethernet ports. Its support for up to 10000 Mbit/s enables high-throughput links for data centre and enterprise networks. The module’s short maximum link distance is suitable for rack-to-rack and within-rack connections, and the lightweight metal housing contributes to thermal stability and mechanical robustness in dense installations.
Suitable for
 Rack-to-rack connections in data centres
 Switch-to-server uplinks requiring 10 Gigabit Ethernet
 Short-reach horizontal cabling within telecom rooms
 Upgrading Dell network equipment to support higher throughput
Key specifications
 Maximum data transfer rate: 10000 Mbit/s
 Interface type: SFP+ (copper)
 Ethernet interface: 10 Gigabit Ethernet
 Ethernet LAN (RJ-45) ports: 1
 Maximum transfer distance: 30 m
 Product colour: Silver
 Weight: 0.02 kg
How to use
Before installation, verify compatibility with the target switch or server, especially Dell equipment if applicable. Power down or follow hot‑swap procedures recommended by the hardware vendor, then insert the SFP+ copper transceiver into an available 10 Gigabit Ethernet slot until it seats firmly. Connect a suitable CAT6/CAT6A copper cable to the RJ‑45 port and configure the network interface in the operating system or switch management software to match the desired speed and duplex settings. Monitor link status LEDs and management interfaces to confirm the link is operational.
Usage recommendations
Use the transceiver for short-distance high-speed links up to 30 m with appropriate shielded or unshielded copper cabling rated for 10 Gigabit Ethernet. Ensure firmware and driver compatibility on connected devices and follow vendor guidelines for hot‑swap and electrostatic discharge protection during handling and installation.

## Specifications

| Feature | Value |
|---|---|
| Interface type | SFP+ |
| Ethernet LAN | Yes |
| Compatible products | 407-BCVC |
| Hot-Plug support | Yes |
| Easy to install | Yes |
| Brand compatibility | Dell |
| SFP transceiver type | Copper |
| SFP transceiver standard | T |

### Other features

| Feature | Value |
|---|---|
| Form factor | SFP+ |

### Operational conditions

| Feature | Value |
|---|---|
| Operating temperature (T-T) | 0 - 70 |

### Weight & dimensions

| Feature | Value |
|---|---|
| Weight | 0.02 kg |

### Ports & interfaces

| Feature | Value |
|---|---|
| Ethernet LAN (RJ-45) ports | 1 |

### Features

| Feature | Value |
|---|---|
| Product colour | Silver |
| Hot-swap | Yes |

### Performance

| Feature | Value |
|---|---|
| Maximum transfer distance | 30 m |

### Network

| Feature | Value |
|---|---|
| Copper ethernet cabling technology | 10GBASE |
| Ethernet interface type | 10 Gigabit Ethernet |
| Maximum data transfer rate | 10000 Mbit/s |

## FAQ

### How much does the Transceiver BlueOptics BO25K859S3D 40G-QSFP-ESR4 cost, and is it available for purchase?

The price is 119.49 € (valid at the time of publication and already includes all taxes). The item is available for order — 86 pcs. are in stock, and you can place your purchase right now with delivery across Latvia and Europe or choose pickup at the Riga collection point. We offer favorable purchase terms, including the option to split the payment into convenient monthly installments. Availability and price are updated in real time, so we recommend placing your order in advance.

### If I order this product today, when will I receive my order?

If you place your order today, delivery will be as fast and convenient as possible. You will be able to pick up your order on 27.08.2026 at the Riga pickup point or choose delivery across Latvia and Europe. We carefully inspect every purchase and pack it securely for safe transportation.

### What payment options are available?

AiO.lv offers several payment methods: Bank transfer. All transactions are 100% secure and encrypted.

### Can this product be purchased for a company (with VAT)?

Yes. AiO.lv works with legal entities in Latvia and across Europe. The product price already includes VAT. For certain product categories, as well as for companies from other EU countries with a valid VAT number, a 0% VAT rate may apply. We issue the invoice immediately after the order is placed, support electronic BIS invoices, and automatically generate all necessary accounting documents. You can complete the purchase for a company online — simply select the company profile and choose bank transfer as the payment method during checkout.

### What is the warranty period?

All BlueOptics products come with an official 2 Years warranty. It covers all manufacturing defects and malfunctions that may occur during use. The warranty is valid at all authorized BlueOptics service centers and through AiO.lv

### Can the product be returned after purchase?

Yes, you can return the product within 14 days of purchase if you bought it as a consumer (not a legal entity). Returns are possible without giving any reason — the main condition is that the product retains its original appearance and full set of accessories. We will make the process as simple and convenient as possible: just contact our customer support team, and we will help you arrange the return.

### Where should I contact for warranty service?

For warranty-related questions you can contact the AiO.lv (SIA VSPRO) customer support team. More information about warranty service: https://aio.lv/en/warranty

### How can I tell if this product suits my needs?

When making a choice, we recommend paying attention to the key features: maximum transfer distance, maximum data transfer rate, compatibility with your devices or usage conditions, material quality, functionality, and warranty terms. These characteristics will help you determine how well the model meets your needs.

## Image

https://aio.lv/img/cache/product/10621321/66006363_large.webp