# K&F Variable Neutral Density Filter K&F X Fader 40.5 mm ND2–ND400 Gray (Model SB7789)

**URL:** https://aio.lv/en/product--kf-sb7789--11878398
**Data updated:** 2026-03-09 20:43 (EET)
**Category:** Camera Filters
**Manufacturer:** K&F
**Manufacturer code:** SB7789
**EAN:** 5904647816749
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 33.99 €
**Prices and availability valid until:** 2026-07-26 23:59
**Price without VAT (21%):** 28.09 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--kf-sb7789--11878398

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 13.07.2026 | free |
| Pickup points | 16.07.2026 | 1.89 EUR |
| Courier delivery to door | 16.07.2026 | 4.99 EUR |

## Summary description

Variable neutral density (ND) filter by K&F, model SB7789, with a 40.5 mm thread and adjustable density range from ND2 to ND400. Designed to reduce light entering the lens for longer exposures, motion blur, and wider aperture control in bright conditions. Gray glass provides neutral color balance. Compatible with lenses using 40.5 mm filter threads.

## Long description

The K&F Variable Neutral Density Filter K&F X Fader 40.5 mm ND2–ND400 Gray is a variable ND filter designed for lenses with a 40.5 mm thread. It provides an adjustable light reduction range from approximately 1 to 9 stops (ND2 to ND400), allowing controlled exposure reduction for long exposures, motion blur effects, and wider aperture use in bright conditions. The gray optical glass maintains neutral color balance to preserve accurate color rendition while reducing incoming light.
Advantages
The variable construction replaces multiple fixed ND filters by offering continuous density adjustment in a single unit, saving space and simplifying workflow. Gray neutral glass minimizes colour cast for faithful color reproduction. The compact 40.5 mm filter profile adds minimal bulk to the front of the lens and is suitable for lightweight camera setups. Mechanical adjustment is fast and precise, enabling smooth transitions between densities for both photo and video applications.
Suitable for
 Long exposures of landscapes and architecture
 Creating motion blur for water, clouds, or moving subjects
 Using wider apertures in bright daylight to control depth of field
 Video shooting requiring adjustable light reduction without changing filters
Key specifications
 Filter thread diameter: 40.5 mm
 Adjustable density range: ND2 to ND400 (approx. 1 to 9 stops)
 Optical material: gray (neutral) glass
 Variable ND mechanism: rotating outer ring to change attenuation
 Profile: slim, low-profile design for minimal vignetting on compact lenses
How to use
Screw the filter onto the lens front thread (40.5 mm) until snug; avoid overtightening. Compose and meter the scene, then rotate the adjustable ring to increase or decrease the density until the desired exposure or motion effect is achieved. For long exposures, use a tripod and remote release or camera timer to prevent camera shake. When using wide apertures, check focus and depth of field as reduced light may require longer shutter speeds or higher ISO.
Usage recommendations
To reduce the risk of cross-polarization or uneven color at extreme settings, avoid using the filter at its maximum density unless necessary; stop down exposure incrementally and verify results on test frames. Store the filter in a protective pouch when not in use and clean optical surfaces with a microfiber cloth and appropriate lens cleaner.

## FAQ

### How much does the K&F Variable ND Filter 40.5 mm SB7789 cost, and is it available for purchase?

The price is 33.99 € (valid at the time of publication and already includes all taxes). The item is available for order — 10 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 13.07.2026 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, Bank cards on-line, Apple Pay, Google Pay. 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 K&F 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 K&F 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/11878398/67295837_large.webp