Ninja

Ninja Double Stack XL SL400UK

Model SL400UK

Best for: Narrow kitchen worktops

MainBuyer overview

What you need to know

A stacked 9.5-litre air fryer designed to offer family-size capacity while using less horizontal worktop space than a conventional side-by-side model. It suits narrower kitchens, although its tall design needs clear space above and around the vents.


Our verdict

One of the most practical options for households that want two-zone capacity but cannot spare the width of a standard dual-drawer fryer.

Reasons to consider it

  • Space-saving stacked layout
  • Large combined capacity
  • Independent zones with synchronised finishing
  • Useful multi-level cooking racks

Things to know

  • Tall body may not fit beneath low cupboards
  • Accessing the lower drawer is less convenient
  • Airflow can require more food repositioning than side-by-side designs

How this review was prepared

This is a research-based MainBuyer assessment using published product specifications and established independent review coverage. We have not claimed hands-on or laboratory testing where none has taken place. The assessment will be updated as more evidence and long-term ownership information becomes available.

Independent approach

Commission rates never determine our editorial ranking or recommendation.

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