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Cybex Sirona Si Comfort i-Size 360 Car Seat - Cozy BeigeCybex Sirona Si Comfort i-Size 360 Car Seat - Cozy Beige
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Cybex

Cybex Sirona Si Comfort i-Size 360 Car Seat - Cozy BeigeOn offer

R67104

339.95£339.95

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  • Free Delivery
  • 365 Day Returns : Return up to Tuesday 26th October 2027.
  • 3 interest-free instalments of £113.32 with PayPal or Klarna

Next Day Delivery Available

- 5-10 Working Days Delivery    

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Boori operate a deposit system: At checkout you will be asked to pay a deposit, with the remaining balance to be paid directly to Boori within 2 working days. Boori will contact you for this payment.

Your purchase of BOORI product(s) is subject to an agreement between you and BOORI UK LIMITED. Please click here to view the full Boori Terms & Conditions.

Keep your little one safe and comfortable with the CYBEX Sirona S i-Size Car Seat, designed for extended rear-facing travel up to approximately 4.5 years. Its protective, energy-absorbing shell helps distribute impact forces, while advanced Linear Side-Impact Protection provides additional protection from side collisions.

The Sirona S combines safety with everyday convenience, featuring smooth one-handed 360° rotation to make getting your child in and out of the car easier. CYBEX GrowTech allows the seat to adapt as your child grows, while the rigid crotch pad and magnetic belt holders make everyday onboarding simple and comfortable.

Suitable from approximately 3 months as standard, the Sirona S can also be used from birth with the optional newborn accessories. An XXL UPF50+ sun canopy***, all-round ventilation and premium Style finishes provide additional comfort throughout your child's early years.

Features:

  • Extended Rear-Facing Safety – Designed for rear-facing travel up to approximately 4.5 years, the Sirona S provides up to 50% better protection* compared with the same seat in a forward-facing position during a frontal impact. Its protective shell helps distribute impact forces while keeping your child securely positioned.
  • Grows Up to 4.5 Years – CYBEX GrowTech allows the seat to grow and adapt with your child. The standard Comfort Inlay provides additional support, while an adjustable headrest and ergonomic M-position help provide a comfortable fit throughout their development.
  • Use from Birth with Optional Newborn Accessories – The Sirona S is suitable from approximately 3 months (61cm) as standard. Optional Newborn Insert and Newborn Inlay accessories allow the seat to be used from birth for babies measuring 40–60cm, providing additional head and body support. Once these are removed, the included Comfort Inlay can continue to be used until your child reaches 85cm.
  • Enhanced Recline Range – AGR-certified for enhanced ergonomics, the Sirona S offers 40% more recline range compared with its predecessor, providing comfortable rear-facing and more upright forward-facing positions as your child grows.
  • One-Handed 360° Rotation – Smooth one-handed 360° rotation allows the seat to turn towards the car door, helping reduce strain on parents' backs when placing their child into or removing them from the seat.
  • Rigid Crotch Pad – The rigid crotch pad stays in position to make getting your child into the seat quicker and easier, providing a more ergonomic experience for both parent and child.
  • Up to 25% More Side-Impact Protection – Advanced Linear Side-Impact Protection (L.S.P.) forms part of a three-tier safety system and is designed to reduce side-impact forces by up to 25%**. Energy is channelled into the car seat's energy-absorbing shell and headrest, while the integrated L.S.P. can be folded away when space is limited.
  • Magnetic Belt Holders – Clever magnets hold the buckle tongues securely at the sides of the seat, keeping the harness out of the way while you place your child into or remove them from the car seat.
  • Optimal Breathability – All-round air ventilation helps keep your child cool and dry throughout the year. Innovative 3D mesh Style fabric self-regulates moisture absorption and increases airflow by up to six times compared with conventional materials, while ventilated hard parts provide additional breathability.
  • SensorSafe Compatible – For additional peace of mind, the Sirona S is compatible with CYBEX SensorSafe, a child-in-car alert system that can monitor conditions and send notifications to your smartphone via the accompanying app.
  • XXL Sun Canopy with UPF50+ – Available on Style colours, the integrated XXL sun canopy provides UPF50+*** protection to help shield your child from sunlight and reduce glare. A breathable mesh window improves airflow, while clever clips allow the canopy to be easily detached when required.
  • Soft on Skin – Materials are screened for restricted and potentially harmful substances, including heavy metals, phthalates and flame retardants. Testing is carried out by internal laboratories and exceeds applicable regulatory testing standards in the markets served.
  • Luxury Design – Style Version Only – Chic two-tone leather-look accents combine with breathable mesh, inspired by premium luxury car interiors. The sophisticated finish provides a combination of style and comfort and is available exclusively in Style variants.

Dimensions:

  • Product Dimensions: L 56 × W 45 × H 55cm
  • Product Weight: 7.3kg
  • Child Height: 61–105cm
  • Child Height with Optional Newborn Inlay: 40–105cm
  • Child Weight: Max. 20kg
  • Child Age: From approximately 3 months up to 4.5 years
  • Use from Birth: Suitable from birth with optional newborn accessories
  • Regulation: UN R129/04
  • Rotation: 360°
  • Installation: Rear-facing and forward-facing
  • Packaging Dimensions: L 74.5 × W 47.5 × H 42cm
  • Gross Packaged Weight: 10.8kg
  • Net Packaged Weight: 7.5kg

* Compared with the same seat in a forward-facing position during a frontal impact, based on internal testing.
** Compared with the same seat without L.S.P., based on internal testing.
*** Except for mesh parts.

Delivery Options & Information

The below delivery options and delivery times only apply once your order is in stock with us. Your order may be on a lead time or pre-order so once the stock is with us, these are your delivery options and timeframes.

Standard Delivery

  • FREE delivery on orders over £50*
  • Orders under £50: £4.99 delivery charge*

*These charges are location dependant, please see our Delivery Info Page for more information

Express Delivery

Our Express Delivery Service is available for £5.99 and can be selected at checkout on eligible products.

  • Available on orders both over and under £50
  • Delivered on the next working day once your order is ready for dispatch
  • Order before 3:00pm for same-day dispatch on in-stock items

Product Availability & Lead Times

The delivery estimate displayed on each product page shows when your item is expected to arrive into stock. All lead times provided are estimates and are based on working days (Monday–Friday, excluding public holidays).

In Stock

Items showing as available for Next Day Delivery are held in our warehouse and can be dispatched the same day when ordered before 3:00pm (Monday to Friday) if you choose the Express service at checkout.

Direct Delivery

Some products are shipped directly from the manufacturer. The estimated delivery timescale will be displayed on the product page.

Supplier Stock Lead Times

Some items are available from our suppliers and are ordered specifically for you. Delivery times vary by product and are clearly displayed on the product page.

Pre-Order Items

Pre-order products can be reserved before they arrive back in stock.

Where an estimated availability date is provided, this is supplied by the manufacturer and may be subject to change. If there are any significant delays, our team will contact you with an update.

Orders Containing Multiple Items

If your order contains items with different lead times, your order will normally be dispatched together once all items are available. This means your estimate delivery date for the full order will be based on the longest lead time in your basket. 

If you would prefer available items to be sent sooner, please contact our customer service team who can arrange this for you.

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