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Maxi Cosi Onyx Booster Seat

Regular price
€249.99
Regular price
€290.00
Sale price
€249.99
Tax included. Shipping calculated at checkout.
A forward‑facing i‑Size car seat for ages 15 months to 12 years, featuring 5 recline positions, integrated ISOFIX with G‑CELL side‑impact protection, and a memory‑foam headrest, growing seamlessly from harnessed seat to high‑back booster.
Colour – Graphite
Product Info

The Maxi Cosi Onyx is a versatile forward facing car seat engineered to accompany your child’s journey from toddlerhood through pre teen years.

Fully compliant with the latest i Size (R129/03) safety regulations, it offers top-tier protection with integrated ISOFIX connectors and G CELL side impact panels, along with a 5 point safety harness for young children—stowable to transform the seat into a convenient high back booster as they grow.

Comfort is prioritized with five incline options, ideal for everything from snack breaks to nap time, and a memory foam headrest that cushions during journeys. The adjustable setup—featuring ten headrest heights and a fully adaptable harness—makes fitting easy as your child grows.

Designed for practical family life, the Onyx is made with 100% recycled “Eco Care” fabrics and features a machine-washable cover (30 °C). The absence of bulky armrests makes buckling effortless—even for independent kiddos.

Weighing around 11kg, it’s a durable yet manageable addition to your vehicle.

Features
  • G-CELL Side Impact Protection: Advanced technology absorbs and disperses crash forces for enhanced safety.
  • 5-Point Safety Harness: Secures children up to 105 cm, then stows away for booster mode.
  • Five Recline Positions: Adjustable settings ensure comfort during every journey.
  • Height-Adjustable Headrest: Adapts to your child's growth for continued support.
  • Eco-Friendly Materials: Covers made from 100% recycled fabrics; machine washable at 30°C.
  • Age Suitability: 15 months to 12 years (76–150 cm)
  • Installation: ISOFIX connectors with top tether
  • Safety Standards: i-Size (R129/03) compliant
  • Dimensions: Height: 52 cm; Width: 30 cm; Depth: 30 cm
  • Weight: Approximately 9–36 kg
  • Product Weight: 11kg
  • Materials: Memory foam headrest; 100% recycled fabric covers
Delivery

Delivery within ROI is free for orders over €30. Orders placed before 1pm will be delivered next working day.

Delivery to UK is free for orders over £80. Orders placed before 1pm will be delivered in 2 working days.

For customers in mainland Europe a shipping rate will be applied at checkout.

Maxi Cosi Onyx Car Seat
Maxi Cosi Onyx Car Seat
Maxi Cosi Onyx Car Seat
Maxi Cosi Onyx Car Seat
Maxi Cosi Onyx Car Seat
Maxi Cosi Onyx Car Seat
Maxi Cosi Onyx Car Seat
Maxi Cosi Onyx Car Seat
Maxi Cosi Onyx Car Seat
Maxi Cosi Onyx Car Seat
Maxi Cosi Onyx Car Seat
Order By 1PM | Next Working Day Delivery
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