Skip to main content
Radian® 3-Across

Radian® 3-Across

The original all-in-one convertible car seat since 2006

Radian® was born when our expert team recognized the need for a better way to prepare for your growing family and busy back seats while keeping your very important passenger as safe as possible.

The original 3-across Radian® features a slimline, space-saving design at only 17” wide that allows you to install three across in most mid to large-sized vehicles in a variety of configurations, from rear-facing to forward-facing with harness.

Engineered with the famous diono® full steel core for maximum safety. This high-strength core has inherent integrity and forms an unyielding structure to shield and protect your child. We didn’t stop there; our aluminum-reinforced sides and thick energy-absorbing foam distribute crash forces to guard your child’s vulnerable side and head, which is critical in side-on collisions.

01

By Crisa

I am in the military and travel a lot. My children (2&3 yrs old) and I were sleeping in the middle seat of a Nissan Armada when we were in a tragic motor vehicle accident on a freeway. This car seat not only save them but also me as I was wedged in the middle of the car seats. I was unconscious while the car caught on fire and I awoke to my children and I upside down. I instantly went into ‘mom mode’ and was able to unbuckle both children with ease while we were upside down and my children and I were able to crawl out one of the windows. Neither one of them had a scratch nor did they have any seatbelt bruising. The car rolled front over back and rotated multiple times leaving us in a ditch upside down. LIFE SAVER.

02

By Eileen

We use Diono Radians for all our kids because of the narrow three across feature. The kids are safe and secure back there! They like them too-- which is awesome because none of them liked the infant bucket seat before they graduated to Radians!

03

By Joseph

Saved all 3 of my children’s lives in a roll over accident everyone came out without a scratch. The police even said normally kids and most adults don’t survive rollovers like ours where we went over a retaining wall and a guard rail. The police said it was the car seats that saved the kids.

04

By Anthony

Bought the purple one for our daughter due in July and will be baby number three. Until then, it’s been being “tested” by our 2yr old son. Purchased it because we already had two car seats from another brand and needed to ensure the third car seat was slim enough to fit in the back. Fits perfectly. It’s HEAVY, but well built. I can’t wait to use the newborn insert. Highly recommend the car seat. I wish I started with this brand for my first child.

Well built and gives peace of mind.

Shop the 3-across family

Radian® 3RXT® SafePlus™ Max

The newest 3 Across All-In-One™ convertible car seat

$399.99

Shop Now

Radian® 3RXT® SafePlus™

Our best selling 3 Across All-In-One™ convertible car seat with SafePlus™ engineering

$299.99

Shop Now

Radian® 3R® SafePlus™

The original 3 Across All-In-One™ convertible car seat with SafePlus™ engineering

$259.99

Shop Now

Radian® 3R®

The original 3 Across All-In-One™ convertible car seat

$259.99

Shop Now

Find the right car seat for you

Radian® 3RXT® SafePlus™ Max

Our newest 3 Across All-In-One™ convertible car seat with SafePlus™ engineering.

  • MSRP - $399.99
  • Slim design to fit 3-across in most mid-size vehicles
  • Reinforced automotive-grade high-strength steel core
  • Rear-facing for longer - from birth up to 50 lb
  • FAA-approved travel-ready foldable car seat
  • Machine washable seat cover
  • One hand easy-adjust 12-position headrest
  • 8-layer aluminum reinforced side impact protection
  • 2-in-1 anti-rebound bar and calf support
Shop Now

Radian® 3RXT® SafePlus™

Our best-selling 3 Across All-In-One™ convertible car seat with SafePlus™ engineering.

  • MSRP - $299.99
  • Slim design to fit 3-across in most mid-size vehicles
  • Reinforced automotive-grade high-strength steel core
  • Rear-facing for longer - from birth up to 50 lb
  • FAA-approved travel-ready foldable car seat
  • Machine washable easy to remove seat cover
  • One hand easy-adjust 12-position headrest
  • 6-layer aluminum reinforced side impact protection
  • Steel anti-rebound bar
Shop Now

Radian® 3R® SafePlus™

The original 3 Across All-In-One™ convertible car seat with SafePlus™ engineering.

  • MSRP - $259.99
  • Slim design to fit 3-across in most mid-size vehicles
  • Reinforced automotive-grade high-strength steel core
  • Rear-facing for longer - from birth up to 50 lb
  • FAA-approved travel-ready foldable car seat
  • Machine washable easy to remove seat cover
  • One hand easy-adjust 12-position headrest
  • 6-layer aluminum reinforced side impact protection
Shop Now

Radian® Accessories

Shop Now