---
product_id: 312123344
title: "AC Infinity Inline Filter Box 4\" with High Efficacy Filter, Whole House HVAC Filtration Kit, Fits 4-Inch Inline Duct Fans for Fresh Air Intake and Ventilation"
brand: "ac infinity"
price: "66074 som"
currency: KGS
in_stock: true
reviews_count: 4
url: https://www.desertcart.kg/products/312123344-ac-infinity-inline-filter-box-4-with-high-efficacy-filter
store_origin: KG
region: Kyrgyzstan
---

# High Efficacy Filter 400 CFM 1mm Steel AC Infinity Inline Filter Box 4" with High Efficacy Filter, Whole House HVAC Filtration Kit, Fits 4-Inch Inline Duct Fans for Fresh Air Intake and Ventilation

**Brand:** ac infinity
**Price:** 66074 som
**Availability:** ✅ In Stock

## Summary

> 🌟 Elevate Your Air Quality Game!

## Quick Answers

- **What is this?** AC Infinity Inline Filter Box 4" with High Efficacy Filter, Whole House HVAC Filtration Kit, Fits 4-Inch Inline Duct Fans for Fresh Air Intake and Ventilation by ac infinity
- **How much does it cost?** 66074 som with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.kg](https://www.desertcart.kg/products/312123344-ac-infinity-inline-filter-box-4-with-high-efficacy-filter)

## Best For

- ac infinity enthusiasts

## Why This Product

- Trusted ac infinity brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Perfect Fit:** Designed to seamlessly integrate with 4” inline duct fans.
- • **Breathe Easy:** Transform your indoor air quality with a robust filtration system.
- • **Built to Last:** Crafted from 1mm thick cold-rolled steel for ultimate durability.
- • **Effortless Access:** Slide lock door for quick and easy maintenance.
- • **Odor & Dust Defense:** High efficacy filter traps dust, dirt, and odors effectively.

## Overview

The AC Infinity Inline Filter Box is a high-performance filtration kit designed for 4-inch inline duct fans, ensuring fresh air circulation while effectively blocking dust and odors. Constructed from durable 1mm cold-rolled steel, it features a user-friendly slide lock door for easy access and a high efficacy filter that captures a wide range of airborne particles. Ideal for enhancing your HVAC system, this filter box is a must-have for maintaining a clean and healthy indoor environment.

## Description

AC Infinity Inline Filter Box 4" with High Efficacy Filter, Whole House HVAC Filtration Kit, Fits 4-Inch Inline Duct Fans for Fresh Air Intake and Ventilation

## Features

- A duct filter box designed for use with inline fans to circulate fresh air and block dust and odors.
- Built with 1mm thick cold-rolled steel and aluminum duct flanges, able to withstand extreme weather.
- Slide lock door gives easy access to inner chamber while soft neoprene layer creates dust-free seal.
- Includes a standard high efficacy filter that traps particles like dust, dirt, lint, and odor.
- 23.46 x 8.42 x 11.73” | Fits 4” Inline Fans | 400 CFM Maximum | Accepts 12 x 20 x 1” Filters

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Brand Name | AC Infinity |
| Model Info | AC-AFB4 |
| Item Weight | 14.12 pounds |
| Product Dimensions | 0.93 x 0.46 x 0.33 inches |
| Item model number | AC-AFB4 |
| Part Number | AC-AFB |
| Compatible Device | CLOUDLINE S4, CLOUDLINE T4 |
| Material Type | Alloy Steel |
| Batteries Included? | No |
| Batteries Required? | No |

## Product Details

- **Brand:** AC Infinity
- **Material:** Alloy Steel
- **Product Dimensions:** 23.46"L x 8.42"W x 11.73"Th
- **MERV Rating:** 13
- **Compatible Devices:** CLOUDLINE S4, CLOUDLINE T4
- **Item Weight:** 6.42 Kilograms
- **UPC:** 819137021693
- **Number of Items:** 1
- **Manufacturer:** AC Infinity
- **Product Grade:** new

## Images

![AC Infinity Inline Filter Box 4" with High Efficacy Filter, Whole House HVAC Filtration Kit, Fits 4-Inch Inline Duct Fans for Fresh Air Intake and Ventilation - Image 1](https://m.media-amazon.com/images/I/41EWnjz-1aS.jpg)

## Available Options

This product comes in different **Size** options.

## Questions & Answers

**Q: what filter fits perfect in the 4" filter box?**
A: the 4" and 6" filters take 12x20x1" filters; the 8 and 10" box's take 14x20x1" filters

**Q: What filter replacement is suggested for the 6" filter box?  standard 20x12x1 does not fit.**
A: Different brands of filters have different "actual" sizes.  Look up the true size of the filter you are using, then check actual filter sizes for different brands that are smaller.

**Q: Do the filters trap smoke from pipes or pollen and mildew?**
A: No, you need a carbon filter for smoke

**Q: Can I use a MERV 17 or HEPA filter instead of a MEV13 filter for additional filtration if they will even fit?**
A: I use the HDX FPR 12 Ultimate Allergen with odor reduction. This filter is a higher end filter.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Great inline air intake filter
*by R***N on November 9, 2023*

After installing an ERV, I noticed the intake air is not sufficiently filtered and that caused PM 2.5 particle counts to go up in the house. This filter is a great solution and I placed it before the ERV to filter the intake air before it reaches the ERV. This has dramatically reduced PM 2.5 particle count back to normal range.It's easy to install and is very solid. It doesn't come with any means to mount the filter or hang it. It's also not insulated so it can condensate if outside air is much colder than inside. I was worried about the box but it was well packaged. Finding the right filter for the 4 in and 6 in version might be a problem, but I think the Home Depot HDX 12X20 MERV 13 filter should fit based on the size of the filter online. But I am using the provided filter at the moment.

### ⭐⭐⭐⭐⭐ I found a replacement filter for the 6" model
*by N***M on December 30, 2022*

We used this 6" model for a fresh make up air for our house. Reading the review we realized people were upset that AC Infinity doesn't sell replacement air filters and those readily available filters at the big box store won't fit.If you are searching for a replacement then buy the Nordic Pure 12x20x1. Amazon sells this brand of filter as well. The actual measurements for this filter is:11.5 x 19.5 x 0.75 inches.Although this air filter is about 0.25-.05 in short on the length and width, it still fit the air box and the seal is still in tact.See pictures for a visual illustration and reference my finger.As for the air box itself, this is a well constructed and high quality air inbox. This is expensive but I believe the quality and craftsmanship justified the price.I hope this review helps.

### ⭐⭐⭐⭐⭐ Awesome build quality on this beauty!
*by J***T on March 24, 2024*

This box looks so good, it's almost a shame I have to mount it in a hidden area.It's solid. It's tough, and the finish is great.The box it was packaged in got heavily damaged in shipping, and the strength of the air handler itself is what saved it from damage. Only a few nicks to the powdercoat finish, no discernible dents, and no affect to the body or door.It latches solidly, seals competently, and comes with a pleated filter already included inside it (independently shrink-wrapped, of course)I also bought a pair of backdraft butterfly dampers (6" as well) from AC Infinity, and their build quality blew me away just as much.I'm really impressed with this company. Yeah, their stuff isn't the cheapest, but you really get what you pay for with these people. I'll be trying to use their products in future projects as often as possible.Highly recommended!!

## Frequently Bought Together

- AC Infinity Inline Filter Box 4" with High Efficacy Filter, Whole House HVAC Filtration Kit, Fits 4-Inch Inline Duct Fans for Fresh Air Intake and Ventilation
- AC Infinity CLOUDLINE PRO S4, Quiet 4” Inline Duct Fan with Speed Controller – EC Motor Ventilation Exhaust Fan for Heating Cooling Booster, Grow Tents, Hydroponics
- AC Infinity Flexible 4-Inch Aluminum Ducting, Heavy-Duty Four-Layer Protection, 8-Feet Long for Heating Cooling Ventilation and Exhaust

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*Product available on Desertcart Kyrgyzstan*
*Store origin: KG*
*Last updated: 2026-01-23*