---
product_id: 312123344
title: "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: "£216.24"
currency: GBP
in_stock: true
category: "Ac Infinity"
url: https://www.desertcart.co.uk/products/312123344-inline-filter-box-4-with-high-efficacy-filter-whole-house
store_origin: GB
region: United Kingdom
---

# MERV 13 high efficacy filter 400 CFM max airflow 1mm cold-rolled steel durability 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:** £216.24
**Availability:** ✅ In Stock

## Summary

> 🌬️ Elevate your air game—because fresh air is the new luxury.

## Quick Answers

- **What is this?** 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?** £216.24 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.co.uk](https://www.desertcart.co.uk/products/312123344-inline-filter-box-4-with-high-efficacy-filter-whole-house)

## 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

- • **Built to Last:** Rugged 1mm cold-rolled steel and aluminum flanges withstand extreme weather and daily wear.
- • **Breathe Cleaner:** High efficacy MERV 13 filter traps dust, dirt, lint, and odors for fresher indoor air.
- • **Effortless Access:** Slide lock door with neoprene seal ensures quick, dust-free filter changes without hassle.
- • **Optimized Airflow:** Supports up to 400 CFM, balancing powerful ventilation with quiet operation.
- • **Seamless Compatibility:** Designed to fit 4-inch inline duct fans including CLOUDLINE S4 and T4 models for easy integration.

## Overview

The AC Infinity Inline Filter Box 4" is a robust HVAC filtration solution featuring a durable 1mm cold-rolled steel body and aluminum flanges. It fits 4-inch inline duct fans, supports up to 400 CFM airflow, and includes a MERV 13 high efficacy filter that effectively traps dust, dirt, lint, and odors. Its slide lock door with a neoprene seal allows for easy, dust-free filter maintenance, making it ideal for whole-house fresh air intake and ventilation.

## 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 - desertcart.com

## 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 |
|---------------|-------|
| ASIN | B0921N33Y7 |
| Best Sellers Rank | #48,341 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #345 in Furnace Filters |
| Brand Name | AC Infinity |
| Compatible Devices | CLOUDLINE S4, CLOUDLINE T4 |
| Customer Reviews | 4.6 4.6 out of 5 stars (332) |
| Item Dimensions L x W x Thickness | 23.46"L x 8.42"W x 11.73"Th |
| Item Weight | 6.42 kg |
| MERV Rating | 13 |
| Manufacturer | AC Infinity |
| Manufacturer Part Number | AC-AFB |
| Material Type | Alloy Steel |
| Model Number | AC-AFB4 |
| Number of Items | 1 |
| Product Grade | new |
| UPC | 819137021693 |
| Unit Count | 1 Count |

## Product Details

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

## Images

![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.

## 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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**Shop now:** [https://www.desertcart.co.uk/products/312123344-inline-filter-box-4-with-high-efficacy-filter-whole-house](https://www.desertcart.co.uk/products/312123344-inline-filter-box-4-with-high-efficacy-filter-whole-house)

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*Product available on Desertcart United Kingdom*
*Store origin: GB*
*Last updated: 2026-08-03*