# Attenuator BlueOptics SFA21XK4 LC 4dB Silver

**URL:** https://aio.lv/en/product--blueoptics-sfa21xk4--11262557
**Data updated:** 2026-03-07 19:55 (EET)
**Category:** Fiber Optic Cables
**Manufacturer:** BlueOptics
**Manufacturer code:** SFA21XK4
**EAN:** 4063232230290
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 53.99 €
**Prices and availability valid until:** 2026-07-21 23:59
**Price without VAT (21%):** 44.62 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--blueoptics-sfa21xk4--11262557

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 23.07.2026 | free |
| Pickup points | 28.07.2026 | 1.89 EUR |
| Courier delivery to door | 28.07.2026 | 4.99 EUR |

## Summary description

The BlueOptics SFA21XK4 attenuator features a 4 dB attenuation level, making it ideal for managing signal strength in fiber optic networks. With LC connectors, it ensures a secure and reliable connection. The sleek silver design adds a professional touch to your setup, while its compatibility with various standards makes it versatile for different applications.

## Long description

The BlueOptics SFA21XK4 LC 4dB Silver attenuator provides a precise 4 dB reduction of optical signal power for multimode fiber links (50/125 µm) at 850 nm. Equipped with an LC/UPC simplex connector and a zirconia ceramic ferrule, this inline passive attenuator is designed to manage excessive transmitter power on short runs or within systems where receiver sensitivity must be protected. The silver housing and LSZH jacket meet industry requirements for installations that demand low smoke and halogen-free materials.
Advantages
The attenuator delivers stable and repeatable 4 dB attenuation with low insertion loss and high return loss thanks to quality polishing and ceramic ferrules. It is manufactured using branded fiber and precision connectors to ensure long life and up to 1500 mating cycles. Each unit is tested with interferometer and OTDR equipment and supplied with measured input loss and return loss values to ensure predictable performance in installed networks.
Suitable for
Reducing transmitter signal power on short multimode fiber links (50/125 µm) at 850 nm
Protecting receivers from oversaturation in data centers and telecom racks
Field installations and patch panels using LC/UPC simplex connectors
Environments requiring low-smoke, zero-halogen cabling materials
Key specifications
Attenuation level: 4 dB (fixed)
Fiber type: Multimode 50/125 µm
Operating wavelength: 850 nm
Connector type: LC/UPC simplex
Ferrule material: Zirconia ceramic
Insertion loss: low (factory measured per unit)
Return loss: high (factory measured; optimized polishing)
Temperature range: -40 °C to +75 °C
Jacket material: LSZH (low smoke, zero halogen)
Durability: up to 1500 mating cycles
How to use
Insert the LC/UPC simplex connector of the attenuator between the transmitter and the receiver or into the patch panel port where signal reduction is required. Ensure connectors and adapters are clean before mating to avoid contamination and increased loss. The device is passive and requires no power or configuration; once installed it provides the rated 4 dB attenuation. If multiple attenuators are used in series, add attenuation values to calculate total loss and verify that the resulting signal level remains within receiver sensitivity specifications.
Usage recommendations
Store and handle the attenuator in a clean environment and use dust caps when not connected. Verify measured loss and return loss values provided with the product against system requirements during installation. Avoid bending the fiber beyond recommended radii and do not expose the attenuator to temperatures outside the specified operating range to maintain performance and longevity.

## Specifications

| Feature | Value |
|---|---|
| Connector(s) | LC |
| Product colour | Silver |
| Temperature range (T-T) | -40 - 75 |
| Attenuation | 4 dB |
| Sustainability compliance | Yes |
| Warranty period | 25 year(s) |
| Compliance certificates | RoHS |

## FAQ

### How much does the Attenuator BlueOptics SFA21XK4 cost, and is it available for purchase?

The price is 53.99 € (valid at the time of publication and already includes all taxes). The item is available for order — 49 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 23.07.2026 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

## Image

https://aio.lv/img/cache/product/11262557/64084142_large.webp