Shark Clean & Empty BU3521UKTSB cordless vacuum with auto-empty dock

1 / 7

Product guide

Shark Clean & Empty BU3521UKTSB cordless vacuum with auto-empty dock

The Shark Clean & Empty BU3521UKTSB is a cordless stick vacuum supplied with an auto-empty charging dock and several cleaning tools. Its practical draw is reduced manual dust-bin emptying, while the stated 40-minute runtime applies only in ECO mode with a non-motorised tool.

At a glance

Auto-empty base is stated to hold dirt and debris for up to 30 days, reducing how often the vacuum needs manual emptying.
The manufacturer claims the sealed base traps up to 99.9% of dust and allergens, citing an IEC test condition in its feature text.
Anti Hair Wrap brush-roll is described as self-cleaning and automatically adjusting for carpets and hard floors.
Detachable handheld vacuum and supplied tools support cleaning beyond floors.
The stated maximum runtime is conditional: ECO mode with a non-motorised tool.

Price

£199.99Save 43%

Reference price: ~~£349.99~~

Price checked: 14 Nov 2026

View offer Ahead of Black FridayExplore the selection

Often bought together

Ring Battery Video Doorbell 2K (newest gen) | DIY Wireless Doorbell Camera, Retinal 2K, 6x Zoom, Two-Way Talk, Easy to install, Built-In Battery

£79.99

Ninja MAX Dual Zone Digital Air Fryer, 9.5L, Stone Gold DZ400UKSTGD | 6 functions: Air Fry, Max Crisp, Roast, Bake, Reheat & Dehydrate. Non-Stick, Dishwasher Safe Drawers.

£239.99

Pros and cons

Pros

Auto-empty charging dock can make routine disposal less frequent than with a manually emptied bin.
Detachable handheld mode and the listed tools cover floor, upholstery and crevice cleaning tasks.
Two speeds and two power levels are listed for adjusting operation.

Technical specifications

18 specifications

Identity
Brand	Shark
Model	Shark Clean & Empty

Cleaning and filtration
Filter type	HEPA Filter
Surfaces listed	Carpets, Hard Floors, Upholstory, in Car, All Floors
Recommended uses	Floor, Pet Hair
Dust capacity	1.3 litres

Power and battery
Power configuration	Battery Powered
Runtime	40 minutes
Number of speeds	2
Voltage	240 Volts
Wattage	240 watts

Dimensions and installation
Form factor	Stick
Weight listed	2.7 Kilograms
Dimensions	35.3L x 26.4W x 109.2H centimetres
Portable	Yes
Indoor/outdoor use	Indoor

Design
Colour	Mohogany
Country of origin	China

What to know before buying

Listing details to confirm

The listing gives a 1.3-litre capacity without clearly distinguishing the base from the vacuum in its details, while feature text specifies 1.3L for the base and 0.42L for the vacuum. It also lists Mohogany as the colour, while feature text says White/Mohogany. The 40-minute runtime is only claimed in ECO mode with a non-motorised tool, and the up-to-30-day base interval is a manufacturer claim, not a guaranteed schedule. Confirm the selected listing's configuration and colour.

What’s in the box

Included

Anti-Allergen Brush
Auto-Empty Charging Dock
Crevice Tool
Motorised Hand Tool
Multi-Surface Tool

Who is it for?

A good fit for

Households wanting an auto-empty dock to reduce frequent manual bin emptying.
Buyers looking for a cordless stick vacuum that converts to handheld use and includes several cleaning tools.
Homes with carpets and hard floors where an anti-hair-wrap brush and automatic floor adjustment are useful.

Less suited to

Anyone relying on 40 minutes of runtime while using a motorised tool or a higher-power mode.
Buyers who need a clearly stated vacuum-bin capacity without resolving the listing's conflicting capacity descriptions.

Shark Clean & Empty BU3521UKTSB cordless vacuum with auto-empty dock · photo 2 — Additional product photo 2

Customer reviews on Amazon

4.3 / 5 · 687 ratings

5 stars70%70%
4 stars14%14%
3 stars6%6%
2 stars2%2%
1 star8%8%

Customer feedback reports positive experiences with cleaning performance, ease of use, lightness, suction and the self-emptying feature, including cleaning kitchen dirt and cat litter. Battery-life experiences are mixed, which matters if you need long sessions away from the dock. The stated 40-minute figure applies only in ECO mode with a non-motorised tool, so it should not be treated as a general runtime. Aggregate ratings lean positive but include a noticeable low-star share, and ratings alone do not explain the reasons behind individual experiences.

Positive themes

Customers report effective everyday cleaning and appreciate the self-emptying feature.
Feedback also highlights ease of use, lightness and suction.

Mixed feedback

Battery-life experiences are mixed.

Frequently asked questions

How long does the Shark Clean & Empty run on a charge?

The listing states up to 40 minutes in ECO power mode with a non-motorised tool. It does not establish that duration for other modes or motorised tools.

What does the auto-empty dock do?

The manufacturer says the sealed base stores dirt and debris for up to 30 days and traps up to 99.9% of dust and allergens. These are listing claims, not independently verified performance.

Can it clean both carpets and hard floors?

The listing names carpets and hard floors, and describes an anti-hair-wrap brush-roll that adjusts automatically to floor type.

What tools are listed as included?

The listed components include an Anti-Allergen Brush, Auto-Empty Charging Dock, Crevice Tool, Motorised Hand Tool and Multi-Surface Tool.