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RC3S vs BU3521UK Cordless Vacuums

Torn between RC3S and BU3521UK for your next cordless vacuum?

RC3S cordless vac
Aeno RC3S
BU3521UK cordless vac
Shark BU3521UK

We examine the RC3S – a battery-power vacuum by Aeno, comparing runtime, dust tank, and costs, with – BU3521UK by Shark, analysing real-world vacuuming performance.

By assessing these vacuums – the RC3S and BU3521UK from AENO and SHARK, you get the best floorcare machine.

Best Cordless Vacuum Pick

Best Pick

Best Buy: Shark PowerPro Cordless Stick Vacuum

Best cordless vacuum – Shark PowerPro – beating RC3S and BU3521UK on performance and value

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AENO RC3S vs SHARK BU3521UK – key Specifications

AENO RC3S Specs

RC3S vacuum specs
  • Product Brand: AENO
  • Cordless Vacuum Model: RC3S
  • Type of Vacuum: Robot
  • Battery Life: 130 Minutes
  • Dirt Tank Capacity: 0.6L
  • Weight: 2.7KG
  • Colour: Black
  • RRP: £399.00

SHARK BU3521UK Specs

BU3521UK vacuum specs
  • Product Brand: SHARK
  • Cordless Vacuum Model: BU3521UK
  • Type of Vacuum: Stick
  • Battery Life: 40 Minutes
  • Dirt Tank Capacity: 0.42L
  • Weight: 2.7KG
  • Colour: Navy Blue & White
  • RRP: £349.99

RC3S and BU3521UK Cordless Battery Run Time

AENO Robot cordless vacuums, like the RC3S, provides lightweight portability without mains cables. BU3521UK Stick is also cordlessly powered by a SHARK rechargeable battery.

The Shark BU3521UK has a battery supply runtime of 40 minutes of cleaning, compared to the Aeno RC3S which has 130 minutes life.

  • AENO RC3S Runtime: 130 mins continuous vacuuming
  • SHARK BU3521UK Runtime: 40 mins continuous vacuuming

Charging times between the RC3S and BU3521UK varies – check manual.

Cordless Vacuum Dust Tank Capacity

Both Aeno RC3S and Shark BU3521UK are bagless, storing dust, hairs, dirt, and debris inside a sealed 0.6 litre and 0.42 litre tank, respectively. The BU3521UK by SHARK holds up to 0.42 Litre of compressed dirty particles. The RC3S by AENO has a capable capacity of 0.6 litre for manual disposable.

  • RC3S onboard dirt/dust tank size: 0.6L
  • BU3521UK onboard dirt/dust tank size: 0.42L

Floor Cleaning Types

Aeno’s RC3S and Shark’s BU3521UK brush heads are effective on every surface – carpets & deep-pile rugs, hard floors (laminate, wood, tiles), vinyl, even upholstery, and stairs.

Their only limitation is the BU3521UK and RC3S can’t vacuum liquids. For this, a SHARK or AENO ‘wet and dry’ vacuum is needed.

Most Aeno and Shark battery powered vacuums include accessories. Check RC3S or BU3521UK manual for specifications and attachments.

Vacuum Filtration

The BU3521UK and AENO RC3S include effective filters to capture dust, dander, pollen, hairs, and fibres.

AENO and SHARK use HEPA, foam, or cloth, filters. RC3S and BU3521UK maintain suction and clean exhaust air.

SHARK and AENO Reviews

Combined feedback from 81 reviewers shows the RC3S with a rating of 4.2/5 stars, and the BU3521UK vacuum gains a 4.4/5 average from 128 reviews, showing comparable reliability results.

BrandModelRuntimeWeightTankBest Price
AENORC3S130 M2.70.6L£399.00
SHARKBU3521UK40 M2.70.42L£349.99
BU3521UK vs RC3S Cordless Vac Specs
Best Pick

Best Buy: Shark PowerPro Cordless Stick Vacuum

Best cordless vacuum – Shark PowerPro – beating RC3S and BU3521UK on performance and value

Limited Offer

Get Deal