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  • For Your Little One Stepup I-Size Isofix 2/3 Car Seat Booster Seat - Midnight Black (4-12 Years-Grade A Return) (Copy)
  • Black high-back car seat with padded headrest, side wings, and green adjustment pads
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  • For Your Little One Stepup I-Size Isofix 2/3 Car Seat Booster Seat - Midnight Black (4-12 Years-Grade A Return) (Copy)
  • Midnight black car booster seat with padded headrest and turquoise adjustment accents
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For Your Little One

For Your Little One Stepup I-Size Isofix 2/3 Car Seat Booster Seat - Midnight Black (4-12 Years-Grade A Return) (Copy)

Good to know i-Size ISOFIX Group 2/3 | Secure Click-In Fit | 4–12 Years
£45.00 £79.99 Save 43% Running low — order soon

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Suitable for children 100–150cm in height (approx. 4–12 years)

Group 2: 15–25kg (approx. 4–6 years) — Forward-facing
Group 3: 22–36kg (approx. 6–12 years) — High-back booster mode

Installation: ISOFIX — check your vehicle is ISOFIX compatible before purchase
Always check your child's height against the seat's headrest guide before use
1x Stepup i-Size ISOFIX Car Seat (Midnight Black)
1x User Manual
✔ i-Size (R129) Certified — Exceeds current EU safety regulations
✔ Rigid ISOFIX connection — click-in installation eliminates fitting errors
✔ Fits children 100–150cm (approx. 4–12 years) — Group 2 & 3
✔ Deep padded side-impact protection wings
✔ One-hand adjustable headrest — multiple height positions, no tools needed
✔ Premium breathable padding for all-day comfort
✔ Removable, machine-washable seat cover

**Please note, this item is a customer return. The item has been checked and all parts are in 'New' condition.

The item may not be shipped in its original packaging.

Customer warranty and rights remain.

Designed to keep your child safe and comfortable from 100 cm to 150 cm (approximately 4 to 12 years), the Stepup i-Size ISOFIX car seat is the last car seat you'll ever need to buy for this stage. Built to the latest UN R129 i-Size safety standard, it delivers superior side-impact protection and a rock-solid ISOFIX connection every single time.

Why Parents Love It

  • i-Size Certified (UN R129) — Exceeds current EU safety regulations for enhanced protection
  • ISOFIX Installation — Rigid, click-in connection eliminates installation errors for total peace of mind
  • Fits 100–150 cm (approx. 4–12 years) — Grows with your child through Group 2 and Group 3 stages
  • Side-Impact Protection — Deep, padded side wings absorb and deflect impact energy away from your child
  • One-Hand Adjustable Headrest — Multiple height positions adapt quickly as your child grows, no tools required
  • Removable, Machine-Washable Cover — Easy to keep fresh and clean
  • Midnight Black Finish — Sleek, premium look that suits any car interior

Safety You Can Trust

The Stepup i-Size meets the stringent UN R129 regulation, which requires extended side-impact testing and a minimum height requirement — giving your child significantly more protection than older Group 2/3 seats. The rigid ISOFIX connection anchors the seat directly to your car's chassis, removing the risk of incorrect belt-only installation.

Comfort for Every Journey

Thick, breathable padding and a one-hand adjustable headrest with multiple height positions mean your child can settle in comfortably whether it's the school run or a long motorway trip.

Specifications

  • Safety Standard: UN R129 (i-Size)
  • Child Height: 100–150 cm
  • Approx. Age: 4–12 years
  • Installation: ISOFIX
  • Facing Direction: Forward-facing
  • Cover: Removable & machine washable
  • Colour: Midnight Black
Black high-back car seat with padded headrest, side wings, and green adjustment pads
For Your Little One Stepup I-Size Isofix 2/3 Car Seat Booster Seat - Midnight Black (4-12 Years-Grade A Return) (Copy)
£45.00
£45.00 -43%
£79.99
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Why you'll love it

Designed around family life

Discover the features, thoughtful details and benefits designed to make life with little ones easier.

i-Size Safety That Exceeds the Standard
01

i-Size Safety That Exceeds the Standard

The Stepup i-Size is certified to UN R129 — the latest and most rigorous car seat safety regulation in Europe. Unlike older Group 2/3 seats, i-Size requires mandatory side-impact testing, meaning your child is protected from impacts that traditional standards don't even test for. Paired with rigid ISOFIX connectors, the seat locks directly into your car's chassis for a secure, error-free fit every time you travel.
For Your Little One Stepup I-Size Isofix 2/3 Car Seat Booster Seat - Midnight Black (4-12 Years-Grade A Return) (Copy)
02

Grows With Your Child From 4 to 12 Years

Covering 100 cm to 150 cm in height, the Stepup takes your child through both Group 2 and Group 3 stages in a single seat — no mid-stage upgrades needed. The one-hand adjustable headrest moves in seconds to match your child's growing height, while the deep padded side wings reposition automatically to keep protection exactly where it's needed at every stage.
Comfort Built for Real Family Life
03

Comfort Built for Real Family Life

The breathable, premium-padded cover keeps them cool in summer and cosy in winter — and when it needs a refresh, simply remove it and pop it in the washing machine at 30°C. The Midnight Black finish looks sharp in any car interior and hides everyday wear beautifully.
Designed for family life Comfort & practicality Made for everyday adventures
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