One car seat designed to support every stage from infant to booster
The Diono Radian 3R All-in-One convertible car seat is designed to grow with your child from the early infant stage through the booster years, giving families one dependable seat for everyday drives, carpools, road trips, and family travel. With a slim profile that can fit 3-across in most vehicles, extended rear-facing capability, reinforced steel core construction, and added comfort features like an infant insert, harness pads, and 2 cup holders, it offers long-term value without compromising convenience or comfort.
10 Years One Car Seat for every stage ahead
Designed to support your child from infant to booster, the Radian 3R All-in-One offers up to 10 years of use in one seat, helping families invest once and stay ready for the years ahead.
Made for a better fit from day one
The included infant insert helps create a more secure and supportive fit for smaller babies, making the transition into everyday travel more comfortable from the start.
Added comfort with harness pads
Soft harness pads help provide a gentler feel around your child’s shoulders and neck while supporting a more comfortable ride on everyday outings and longer drives.
2 cup holders for everyday convenience
Integrated cup holders help keep drinks, snacks, or small travel essentials within easy reach, making everyday rides and family trips more convenient for both kids and parents.
Rear-facing for longer
Supports rear-facing use up to 50 lb, helping families keep little ones in the rear-facing position longer through the early years.
All-in-1 convenience in one seat
Use the Radian 3R All-in-One in rear-facing, forward-facing, and booster modes, giving growing families one practical all-in-one solution instead of replacing seats as children move through different stages.
Slim fit design that can fit 3-across in most vehicles
The signature Diono narrow profile is designed for busy back seats, helping fit 3 car seats across in most vehicles while still giving your child a comfortable place to ride.
Reinforced steel core construction
Built with a mechanically engineered reinforced steel core made from automotive-grade high-strength steel to help provide dependable strength and protection on every drive.
FAA approved for aircraft use in harness mode
Travel with more confidence knowing the Radian 3R All-in-One is approved for use on aircraft when used with the 5-point harness in rear-facing or forward-facing mode, making it a practical choice for family travel beyond the car.
Comfort for everyday rides, errands, and road trips
From school drop-offs and quick errands to longer family drives, the deep supportive seat design helps create a more comfortable ride for growing children at every stage.
Machine washable cover for easier cleanup
Real family life gets messy. The easy-remove fabric cover is designed for simpler cleanup after everyday spills, crumbs, and snack-time accidents.
A practical choice for growing families
Whether you’re planning for the newborn stage, managing multiple children, or trying to make the most of a smaller back seat, the Radian 3R All-in-One combines long-term use, a compact footprint, and thoughtful comfort features in one versatile convertible car seat.
Use range
Rear-facing: 5–50 lb (2.3–22.7 kg)
Forward-facing: 26.5–65 lb (12–29.5 kg)
Booster mode: 40–120 lb (18–54 kg)
Maximum child height: up to 57 in (144.8 cm)
Aircraft use note
FAA approved for use on aircraft in rear-facing and forward-facing harness mode
