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Shark says that the enhanced brush-roll design on the Stratos IZ400UKT delivers best ever hair pick-up. To see if our tests can confirm these claims, we sent it to the lab. Read the full review to see how well this cordless vacuum performs on carpets, hard floors and whether it can efficiently deal with pet hair.
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What's included?
- What is it?
- How well does it clean?
- How easy is it to use and maintain?
- Is there anything I should know?
- Should I buy it?
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| Carpet cleaning | |
|---|---|
| Laminate floor cleaning | |
| Pet hair removal |
- Dec 2022First reviewed by Which?
The overall Which? test score is made up of the following star ratings, all determined by our rigorous lab tests.
Carpet cleaning
How we test carpet cleaning
This score shows how well the vacuum cleaner sucks up fine Arizona desert sand from deep within the pile of Wilton carpets. The best models will suck up as much as eight times more than the worst.
Allergen retention
How we test allergen retention
This test is particularly important for serious allergy sufferers who want to remove all of the fine dust and allergens they can from their home. A five-star score here means that nearly all of the fine dust and allergens that the vacuum cleaner picks up are locked tightly within the container and are not released back into the home.
Cleaning with a full dust container
How we test cleaning with a full dust container
How well the vacuum sucks up dust from crevices when the dust container is full. If you want to compare how well this vacuum cleans when the vacuum is full, and empty, then compare the floorboard star rating, with this one.
Noise
How we test noise
The more stars the quieter this model is compared to others we have tested.
Battery life and recharging
How we test battery life and recharging
The best batteries last for up to an hour and don't take long to recharge. The worst will give you less than twenty minutes of power and take more than half a day to fully recharge.
Energy consumption
How we test energy consumption
How much energy the cordless vacuum cleaner uses, both while in use and also in standby mode.
Ease of Use
| Overall | |
|---|---|
| Maintenance | |
| Versatility | |
| Vacuuming at height | |
| Handling and controls | |
| Cleaning stairs | |
| Vacuuming on upholstery | |
| Vacuuming on carpet | |
| Vacuuming on hard floor | |
| Vacuuming on uneven surfaces |
How we test ease of use
How easy it is to regularly clean and maintain the vacuum cleaner including changing and replacing filters and emptying and cleaning the dust canister.
Floorboard cleaning
How we test floorboard cleaning
This score shows how well each cordless vacuum cleaner picks up dust from in between the crevices that you find between traditional floorboards. While some cordless vacuums will comfortably suck up dust from a flat hard surface, floorboards with deep crevices often prove a lot more challenging.
Laminate floor cleaning
How we test laminate floor cleaning
This score shows how well each cordless vacuum cleaner sucks up fine dust from hard flat floors such as laminate. A five-star score here means that your hard flat floors will be left spotless.
Large debris
How we test large debris
This score shows how well each cordless vacuum cleaner sucks up large debris, like rice and lentils, from flat hard surfaces. A five-star score here means that your hard flat floors will be left spotless of any large debris, one-star means much will be left behind or scattered around the floor.
Pet hair removal
How we test pet hair removal
Pet owners will want to play close attention to the results of this test. First we comb real cat and dog hair into a section of carpet to simulate how trodden in and engrained it can get in a real home. We then time how long it takes each cordless vacuum cleaner to suck it all up. A great cordless vacuum cleaner can suck it all up in less than 20 seconds, the worst leave hair behind even after two minutes of continuous cleaning.
Fibre removal
How we test fibre removal
How quickly the cordless vacuum cleaner can suck up lint and fibres from upholstery.
Cleaning on minimum power
How we test cleaning on minimum power
How well the vacuum cleaner cleans on flat hard floors on its minimum power setting. 1 star means that the cordless vacuum is almost ineffective on its minimum setting, whereas 5 star means you will get excellent results even when maximising your cordless vacuums battery life.
Floor coverage
How we test floor coverage
This score shows you how close to walls and corners the floorhead cleans. Some cordless vacuum cleaners have suction channels that do not extend right to the edges of the floorhead and so can leave large uncleaned margins around the edge of rooms. The more stars, the closer the floorhead gets to the edges.
| General | |
|---|---|
| Type | Cordless |
| Bagged or bagless | Bagless |
| Dust capacity | 0.9 litres |
| Weight | 4.1kg |
| Weight in context | Average weight |
| Detachable handheld | Yes |
| Battery life on minimum power | 0hr 54mins |
| Battery life on maximum power | 10 mins |
| Charging time | 3hrs 38mins |
| Run time in context | 30 to 60 mins runtime |
| Can you replace the battery yourself? | Yes |
| Maximum push force in Newtons on medium pile carpet | 13 |
| Maximum push force in Newtons on plush pile carpet | 14 |
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TESTING IN NUMBERS
110
Cordless vacuum cleaners48
Best Buys16
Don't BuysHow this product's score compares with other cordless vacuum cleaners we've tested
32%Lowest score
63%Average score
%This product
86%Highest score
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