Keeping your child rear-facing for as long as possible is one of the most effective safety choices you can make, and the Cybex Sirona S i-Size is built to make that easy. This rear-facing car seat is designed for travel up to around 4.5 years, with extra side impact protection and a 360° rotation that makes getting your child in and out far simpler. It is part of the Cybex Platinum S-Line modular system and is fitted using the Base S.
Rear-Facing Safety for Up to 4.5 Years
Rear-facing travel is mandatory until your child is 15 months old, and the Sirona S lets you carry on well beyond that. The shell works like a protective cocoon, spreading impact forces and holding your child close in a collision. Cybex reports up to 50% better protection than the same seat used forward-facing in a frontal impact, based on internal testing. For parents who want to keep their child rear-facing for the longest possible time, that is a very reassuring starting point.
Protection Built Around Side Impact Safety
Side collisions are a real concern, and the Sirona S addresses them with Linear Side-Impact Protection. This channels energy into the energy absorbing shell and headrest, and it can reduce impact forces by up to 25% compared with the same seat without it, based on Cybex internal testing. The protection folds out with a simple push during setup, then tucks neatly away when space is tight. The seat meets UN R129/04, and its materials are screened for harmful substances including heavy metals, phthalates and flame retardants.
Smooth Rotation for Easier Everyday Journeys
Lifting a growing child in and out of a rear-facing seat can be hard work. On the Base S, the Sirona S rotates a full 360° with one hand, so you can place your child in from the side and avoid awkward twisting. A rigid crotch pad makes it simpler to position them, and magnetic belt holders keep the buckle tongues tucked neatly out of the way while you buckle up. These small details make school runs and busy mornings noticeably calmer.
Designed to Grow With Your Child
Cybex GrowTech lets the seat adapt as your child gets taller, suiting heights from 61cm to 105cm. The Comfort inlay is included and provides soft, adaptive support until your child reaches 85cm. To use the seat from birth, you can add the Newborn insert and inlay, which are available as accessories for babies measuring 40 to 60cm. The seat is AGR certified for ergonomics, with an adjustable headrest and a natural M-position. It also offers a 40% wider recline range than its predecessor in rear-facing, as well as more upright forward-facing positions.
Cybex Sirona S i-Size Comfort Key Features
- Rear-facing car seat for children from approximately 3 months up to 4.5 years
- From birth with the Newborn insert and inlay accessory (40 to 60cm)
- Suitable for children from 61cm to 105cm in height, up to a maximum of 20kg
- Up to 50% better protection than forward-facing travel in a frontal impact*
- Linear Side-Impact Protection (L.S.P.) for up to 25% more side impact protection**
- One-handed 360° rotation on the Base S
- Rigid crotch pad for simple onboarding
- Magnetic belt holders keep the buckle tongues out of the way
- Cybex GrowTech with adjustable headrest and M-position
- AGR certified for ergonomics
- Comfort inlay included for use until the child reaches 85cm
- Materials screened for harmful substances
*Compared to the same seat in a forward-facing position during a frontal impact, based on internal test results. **Compared to the same seat without L.S.P., based on internal testing.
Cybex Sirona S i-Size Comfort Specifications
Product Dimensions: L 56cm / W 45cm / H 55cm
Weight: 7.3kg
Suitability: From approximately 3 months up to 4.5 years (from birth with newborn inlay accessory)
Child Height: 61 to 105cm (40 to 60cm with newborn inlay)
Maximum Child Weight: 20kg
Safety Standard: UN R129/04
Compatible Base: Cybex Base S
Packaging Dimensions: L 74.5cm / W 47.5cm / H 42cm
Gross Weight: 10.8kg
Net Weight: 7.5kg
