BU3523 BU3521 BU3120 HEPA Filter 7-Pack Replacement - Value Pack

In this review of the NIXOOT 7-pack replacement filters, the bottom line is simple: this set is for owners of the Shark BU3523, BU3521 or BU3120 cordless stick vacuums who want a convenient, cost-effective way to keep suction and filtration consistent between cleanings. The reviewer found the package covers both handheld and auto-empty system needs, provides washable HEPA elements that capture fine dust, and is easy to swap in without tools, making it a practical routine maintenance purchase for households that use their cordless cleaner frequently.

Key Features

• Compatible Model: Specifically designed to fit BU3523, BU3521 and BU3120 cordless stick vacuums so users can replace worn parts with confidence.
• Value Pack: Includes two handheld pre-motor filters, two auto-empty HEPA filters and two pre-motor filter assemblies with foam and felt so you get multiple spares in one purchase.
• Washable and Reusable: Filters can be cleaned manually and reused several times, extending service life and helping maintain suction between replacements.
• Premium Material: Made from high-toughness HEPA filter paper and durable ABS components to trap particles down to 0.3 microns, including pollen and allergens.
• Easy Installation: No tools required to remove and replace the parts, which speeds routine maintenance and reduces downtime for cleaning tasks.

Who It's For

This replacement set is aimed at owners of the supported Shark cordless models who prefer to do their own maintenance and want a complete set of both handheld and auto-empty system filters in one purchase. It suits households with pets or allergy concerns where frequent filter changes help preserve air quality and vacuum performance.

Those who should look elsewhere include people who do not own the specified models or who expect machine-washable filters only; these filters are intended for manual cleaning and scheduled replacement rather than laundry-style washing.

Pros & Cons

Pros

• Complete replacement kit covers handheld and auto-empty system needs, reducing the need to buy parts separately.
• Washable HEPA media and durable ABS parts offer multiple uses before replacement, lowering long-term cost.
• Filters claim to block up to 99.97% of particles as small as 0.3 microns, helping with allergen control.

Cons

• Filters must be cleaned manually rather than machine washed, which requires a little extra care and time.
• The set is specific to certain Shark models, so it is not universal and will not fit other vacuum lines.

Specifications

Brand	NIXOOT
Compatible Models	BU3523, BU3521, BU3120
Pack Contents	2 pre-motor handheld, 2 auto-empty HEPA, 2 pre-motor foam/felt assemblies (7 total pieces)
Filter Type	HEPA filter paper with ABS frame
Particle Capture	Up to 99.97% of particles down to 0.3 microns
Cleaning	Manual cleaning; not machine washable
Recommended Replacement	Replace set every 3 months for best performance

Our Verdict

The NIXOOT 7-pack is a practical maintenance kit for owners of BU3523, BU3521 and BU3120 cordless vacuums who want to keep filtration and suction consistent without hunting for individual parts. It delivers good value by combining handheld and auto-empty system filters, uses HEPA media that helps with allergens, and installs without tools, making it a sensible purchase for routine upkeep.

Frequently Asked Questions

Are these filters compatible with my Shark BU3523?
Yes, the set is designed specifically for BU3523, BU3521 and BU3120 models.

Can I machine wash the HEPA filters?
No, the filters are washable by hand but are not machine washable and should be dried completely before reinstalling.

How often should I replace the filters?
The manufacturer recommends replacing the filter set every three months for optimal performance, though reusable filters can be manually cleaned between replacements.