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      • Britax Roundabout 55 - Onyx


        The Britax Roundabout 55 convertible car seat is designed for children rear facing from 5 to 40 pounds and forward facing from 20 to 55 pounds. The Roundabout 55 achieves revolutionary head safety through the use of Britax SafeCell Technology in the base, integrated steel bars, and energy absorbing Versa-Tether that work together to minimize head excursion and reduce the risk of head injury during a frontal impact. The Roundabout 55 also incorporates Britax Side Impact Protection, offers a five-point harness, and multiple buckle and recline adjustments. A body pillow is provided for extra comfort and infant positioning.

        Recommended Age:Newborn, Baby, Toddler

        Features:

        • Base with SafeCell Technology features SafeCells designed to compress in a crash, significantly lowering the center of gravity and counteracting the forward rotation of the child seat which normally propels the child toward the front seat
        • Integrated Steel Bars strengthen the connection to the vehicle and reduce forward flexing of the child seat during a crash
        • Energy-Absorbing Versa-Tether features a staged-release tether webbing to slow the forward movement, reducing the crash forces reaching the child, and a two-point attachment to minimize forward rotation while anchoring the top of the child seat
        • Side Impact Protection comprised of deep side walls lined with energy-absorbing EPP foam distributes crash forces, shields from vehicle intrusion, and contains the head, neck and body
        • Tangle-Free, Five-Point Harness distributes crash forces across the strongest parts of the body and provides a secure fit
        • 55-pound Weight Capacity for safety and comfort as your child grows
        • Rear and Forward Facing Recline for child comfort and positioning
        • High Density Comfort Foam provides an extra layer of padding to gently cushion your child
        • Two Buckle Positions for your growing child
        • Infant Positioning Insert may be necessary for small infants to achieve a snug fit of the harness around your child (sold separately)
        • Premium Lower LATCH Connectors for a quick and simple installation featuring a push button for easy release
        • Built-in Lock-Offs ensure a snug lap and shoulder belt installation with minimal effort
        • Anti-Slip, Contoured Base grips and protects the vehicle seat while offering optimum vehicle fit
        • Harness Holders keep harness straps pulled to the sides when placing your child in the car seat
        • Certified for Aircraft Travel
        • Made in the USA with global components

        • 100% Polyester



      • Product Dimensions: 18.5 W x 26 H x 21 D

        Product Weight: 17.6

        Manufacturer Model Number: E9LJ11A

      Product Notes

      View All Britax View All Car Seats

      Britax Roundabout 55 - Onyx

      37 reviews
      $149.99
      List Price: $199.99
      Sale! (You Save 25%)
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      PRODUCT REVIEWS AND RESOURCES

      We've collected resources from around the web to help you make your purchasing decisions.

      Review Snapshot

      REVIEW SNAPSHOT®

      by PowerReviews
      BritaxRoundabout 55 - Onyx
       
      5.0

      (based on 8 reviews)

      100%

      of respondents would recommend this to a friend.

      Pros

      • Comfortable (7)
      • Durable (5)
      • Easy to install (5)
      • Safe (5)
      • Easy to adjust (4)

      Cons

        Best Uses

        • Toddler (6)
          • Reviewer Profile:
          • First time parent (4), Parent of two or more children (4)

        Reviewed by 8 customers

        Sort by

        Displaying reviews 1-8

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        5.0

        Good Quality and Comfortable

        By Eileen

        from San Jose, CA

        About Me First Time Parent

        Pros

        • Comfortable
        • Easy to Adjust
        • Easy to Clean
        • Easy to install
        • Lightweight

        Cons

          Best Uses

          • Toddlers

          Comments about Roundabout 55 - Onyx:

          I bought this carseat after doing a lot of research. I also own a infant carrier from Britax and knew I wanted to buy a convertible car seat from them also.

          One of the main reason why I bought this was because it fits in my small sedan car (Lexus IS250). My son has enough room for his legs and the carseat does not seem as bulky as the other ones I've seen. It is not too heavy, so it's easy to move and install in my husband's car when needed. My son loves being in this car seat and falls right a sleep with no problem.

          Comment on this review

           
          5.0

          Perfect Fit!

          By LaniDada

          from Concord, CA

          About Me First Time Parent

          Verified Buyer

          Pros

          • Comfortable
          • Easy to Adjust
          • Easy to install
          • Safe
          • Sturdy
          • Stylish

          Cons

            Best Uses

              Comments about Roundabout 55 - Onyx:

              I knew Britax was one of the top Brands for baby safety, and I did my research on all Brands. In the end, I chose Britax. I already have the Britax Marathon 70 (RF) for my car, and this purchase was for my Mother-n-law's car. Her car is a Ford Focus, which we all know is a bit small in the back; but the Britax Roundabout was a perfect fit. We love this carseat because of the recline features as well as the durability of the entire seat.

              Comment on this review

               
              5.0

              Truly perfect

              By Brian the dad

              from Biloxi Mississippi

              About Me Parent of Two or More Children

              See all my reviews

              Verified Buyer

              Pros

              • Comfortable
              • Safe
              • Sturdy
              • Stylish

              Cons

              • Difficult To Adjust

              Best Uses

              • Toddlers

              Comments about Roundabout 55 - Onyx:

              I now own 2 of these exact seats they are perfect and seem very safe. I also own a marathon and but it was a gift and is defiantly better but cost a good bit more. This seat fits my budget and is safe. Only down fall of it is moving it from car to car. That's why I bought 2.

              Comment on this review

               
              5.0

              Awesome Car seat!!!

              By JesseK

              from Eastern Ky

              About Me Parent of Two or More Children

              Verified Buyer

              Pros

              • Comfortable
              • Easy to Adjust
              • Easy to Clean
              • Easy to install
              • Lightweight
              • Safe
              • Sturdy
              • Stylish

              Cons

                Best Uses

                • Infants
                • Toddlers

                Comments about Roundabout 55 - Onyx:

                This car seat is amazing! Yes that's right I said amazing! It is so sturdy and so secure that it's unbelievable!! You can try to move it and if its installed in the vehicle properly it doesn't budge! I love it! My son loves it! Well worth the money! Also the size is excellent I have a 2013 Mazda cx5 which is a crossover not a small vehicle but its on the smaller side and this car seat fits excellent! I have tons more room in my back seat with it! Thank you thank you thank you!!! We love it!

                Comment on this review

                 
                5.0

                Great seat

                By Brian the dad

                from Biloxi Mississippi

                About Me Parent of Two or More Children

                See all my reviews

                Pros

                • Comfortable
                • Easy to Clean
                • Safe
                • Sturdy
                • Stylish

                Cons

                • Difficult To Adjust
                • Hard to Install

                Best Uses

                • Toddlers

                Comments about Roundabout 55 - Onyx:

                I'm a dad that had to buy his own car seat ( My wife claimed the one my mom bought me for our son go figure). I bought this seat around 4 months ago and really like it. My mom bought us the marathon and we loved it also. I'm judging this seat against it which is bout 70 bucks more. This seat is really the way to go !!!! It very high quality but a pain in the real to move from vehicle to vehicle . So I just purchased my second to have in my truck ( we have 3 vehicles). Overall this seat is very safe and well built I can not overstate how great this seat is . Buy this one and keep your baby safe. Trust me it will.

                Comment on this review

                 
                5.0

                LOVE IT!

                By F. Lopez

                from Fort Hood, TX

                About Me Parent of Two or More Children

                Verified Buyer

                Pros

                • Comfortable
                • Easy to install
                • Fits In Compact Car

                Cons

                  Best Uses

                  • Toddlers

                  Comments about Roundabout 55 - Onyx:

                  My car is rather small and I was looking for a seat that would fit well rear-facing. This one fits PERFECTLY! My son is also very comfortable and installation was a breeze!

                  Comment on this review

                   
                  5.0

                  great car seat

                  By Ruby

                  from san diego, CA

                  About Me First Time Parent

                  Verified Buyer

                  Pros

                  • Comfortable
                  • Easy to Adjust
                  • Easy to Clean
                  • Easy to install
                  • Safe
                  • Sturdy

                  Cons

                  • Heavy

                  Best Uses

                  • Toddlers

                  Comments about Roundabout 55 - Onyx:

                  great car seat

                  Comment on this review

                  (1 of 2 customers found this review helpful)

                   
                  5.0

                  Good Car Seat

                  By MiniMini

                  from Philadelphia

                  About Me First Time Parent

                  See all my reviews

                  Verified Buyer

                  Pros

                    Cons

                      Best Uses

                        Comments about Roundabout 55 - Onyx:

                        I would recommend watching the Britax install video - you will probably pool noodles if you are installing refar acing.

                        Comment on this review

                        Displaying reviews 1-8

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