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Britax Marathon 70-G3 Convertible Car Seat - Onyx

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Britax Marathon 70-G3 Convertible Car Seat - Onyx - Britax  - Babies"R"Us
  • $289.99
  • $259.99
  • Ship-To-Home
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  • +$59.99

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  • This Item is included in our Car Seat Finder Comparison Tool
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  • Gift givers, please note that this item may be shipped in the manufacturer's original packaging, which may reveal what's inside.

  • Product is not available for shipping internationally. (Details)

  • This item is only sold online and is not available in our stores.

Special Offers

Only $19.99 Britax 3-in-1 Car Seat Accessory Kit when you buy a select Britax Convertible or Harness-2-Booster Car Seat - (Details)
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Product Description

The Britax Marathon 70-G3 Convertible Car Seat ? Onyx accommodates children rear facing from 5 to 40 pounds and forward facing from 20 up to 70 pounds. The Marathon 70-G3 is purposefully designed and engineered to minimize the forward movement of your child's head during a frontal impact to reduce the risk of head injury with the following revolutionary Britax head safety technologies: Base with SafeCell Technology designed to compress in a crash, significantly lowering the center of gravity and counteracting the forward rotation of the child 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 two-point attachment and staged-release tether webbing to slow the forward movement and reduce the crash forces reaching the child. The Marathon 70-G3 also incorporates Britax Side Impact Protection to contain the child and protect from the most severe types of crashes. The five-point harness is tangle-free with an EZ-buckle system to retain the harness buckle in a forward position and harness holders that keep harness straps pulled to the sides to make boarding quick and hassle-free. Other features include a no-rethread harness and an easy-remove cover that also allows access to belt paths from the front of the seat, while the multiple buckles and recline positions, comfort pads, and infant body pillow provide premium comfort and positioning.

Britax Marathon 70-G3 Convertible Car Seat ? Onyx Features:

  • Base with SafeCell Technology
  • Integrated Steel Bars
  • Energy Absorbing Versa-Tether
  • HUGS (Harness Ultra Guard System) Chest Pads
  • Side Impact Protection
  • Five-point harness
  • Multiple buckle and recline positions

This and all items from Britax are excluded from all promotions and discounts except where otherwise noted on product detail pages.

Features

  • Base with SafeCell Technology 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
  • HUGS (Harness Ultra Guard System) Chest Pads provides resistance to forward movement in the event of a crash
  • 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

Additional Info

889247

DF36684A

652182071004

E9LJ51A

21 x 18.5 x 26

5 lbs

70 lbs

Convertible

Latch,5 Point Harness,Front Adjusters,Adjustable Head Support,Washable Fabric

Yes

22.4 pounds

29.5 x 19.3 x 18.5

How to Get It


  • This item can be shipped to the entire United States including Alaska, Hawaii, and all U.S. territories including Puerto Rico
  • This item can also be shipped to APO/FPO addresses and to P.O. Boxes in all 50 states
  • Due to shipping restrictions, Ship Charges will be separate from other items in your order
  • This item will ship by itself


  • This item may be shipped via Standard Shipping, Expedited Shipping or Express Shipping
  • Please Note: Some addresses are eligible for Standard Shipping only (APO/FPO, P.O. Boxes, U.S. Territories and Puerto Rico)

(learn more):

  • This item is sold online only (not sold in stores)
  • Orders placed for Store Pickup will receive online pricing and promotions
  • In-stock status is approximate and may not reflect recent sales
  • Not all items are carried at all stores. Please click the "Select a store" link to check product availability
This item may be shipped in the manufacturer's original packaging, which could reveal the contents of the box

Average Customer Rating:

by PowerReviews
Britax Marathon 70-G3 Convertible Car Seat - Onyx
 
4.1

(based on 8 reviews)

Ratings Distribution

  • 5 Stars

     

    (4)

  • 4 Stars

     

    (2)

  • 3 Stars

     

    (1)

  • 2 Stars

     

    (1)

  • 1 Stars

     

    (0)

75%

of respondents would recommend this to a friend.

Pros

  • Easy to adjust (6)
  • Safe (6)
  • Comfortable (5)
  • Durable (5)
  • Easy to install (5)

Cons

  • Heavy / bulky (5)
  • Heavy (4)

Best Uses

  • Toddler (6)
    • Reviewer Profile:
    • First time parent (5)

Reviewed by 8 customers

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Displaying reviews 1-8

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3.0

Nothing to compare it to…..but…..

By New Mama

from Phoenix, AZ

About Me First Time Parent

Pros

  • Easy to Adjust
  • Easy to install

Cons

  • Bulky
  • Heavy
  • Poor Construction

Best Uses

  • Toddlers

Comments about Britax Marathon 70-G3 Convertible Car Seat - Onyx:

I bought this as a front rider car seat for my toddler and was very excited to get an open-box price! It has been 5 months since my purchase and here are the things I do not like about the chair.
* The removable padded inserts do not stay put when in place
* The rubber belt protector/strap broke
* The straps are constantly twisting
* The straps that have the velcro on them to velcro to the sides of the seat (to help load baby in not on them) do not align easily and it takes manipulating.

Comment on this review

(0 of 6 customers found this review helpful)

 
4.0

Looking forward to using it!

By Almost a Mommy

from Winston-Salem, NC

About Me First Time Parent

See all my reviews

Verified Buyer

Pros

  • Stylish

Cons

    Best Uses

      Comments about Britax Marathon 70-G3 Convertible Car Seat - Onyx:

      The only reason I didn't give this product 5 stars is because I haven't got to see it in action yet. I just received it via UPS but am very satisfied by it's appearance. We ordered it online because we liked the Onyx pattern better than the one carried in-store. Very pleased with the pattern in person, it is just as it appears online.

      Comment on this review

       
      5.0

      Love love love!!

      By Shelly

      from San Antonio, TX

      About Me Parent of Two or More Children

      Pros

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

      Cons

        Best Uses

        • Newborn
        • Toddlers

        Comments about Britax Marathon 70-G3 Convertible Car Seat - Onyx:

        We bought this one after our daughter outgrew her infant carrier and absolutely love it! It doesn't get any better. It's sturdy and our daughter fits perfect in it. I would recommend this to anyone who is looking for a car seat.

        Comment on this review

         
        4.0

        5yrs and still using it

        By working mom

        from ca

        Pros

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

        Cons

        • Bulky
        • Heavy

        Best Uses

          Comments about Britax Marathon 70-G3 Convertible Car Seat - Onyx:

          We bought this car seat for my daughter after she out grew her infant seat. She is 5 1/2 yrs old and is still using it. She is tall for her age and does not complain about the car seat being too small or snug.

          Comment on this review

          (7 of 11 customers found this review helpful)

           
          2.0

          ONLY upto 40lbs. Buckles are TOO short.

          By Blue

          from Nyack, NY

          About Me Parent of Two or More Children

          Pros

          • Safe
          • Sturdy

          Cons

          • Bulky
          • Heavy
          • Uncomfortable

          Best Uses

          • Toddlers

          Comments about Britax Marathon 70-G3 Convertible Car Seat - Onyx:

          Because of side protection & 70lb weight capacity which my husbands liked about, we purchased all three car seats from Britax for our kids - one Boulevard for our girl(5yrs)and two Marathon for our boys (3yrs &16month).
          Even though these were too bulky & cost a lot, I thought it's ok since these offer safety for my kids (according to description of product). And these seems fine until my kids grow around 40lb & 3yrs old.

          Now I am not sure whether we made right decision to purchase these. The buckle is already too short for my boy who is just 3yrs old & less then 37lb. And of course, my girl who is 5yrs & 44lbs, always complains about how uncomfortable she is with SHORT buckle. Frequently I ended up let her not buckle lower one.

          I definitely wouldn't recommend to purchase these.

          Comment on this review

          (7 of 8 customers found this review helpful)

           
          5.0

          Best car seat ever

          By coco

          from canada

          About Me First Time Parent

          Pros

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

          Cons

          • Bulky
          • Hard to Install

          Best Uses

          • Toddlers

          Comments about Britax Marathon 70-G3 Convertible Car Seat - Onyx:

          We bought this for my son after he turned 1 and this has been the most confortable car seat ever. He is 4 now but tiny and still uses it.

          Comment on this review

          (4 of 4 customers found this review helpful)

           
          5.0

          EXCELLENT CAR SEAT

          By Stephany

          from Atascadero, CA

          About Me First Time Parent

          Pros

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

          Cons

          • Bulky
          • Heavy

          Best Uses

          • Infants
          • Newborn
          • Toddlers

          Comments about Britax Marathon 70-G3 Convertible Car Seat - Onyx:

          Great carseat. This car seat is sturdy and safe. The fabric is easily washable. I love this car seat and so does my son.

          Comment on this review

          (17 of 18 customers found this review helpful)

           
          5.0

          Love it!

          By First Time Mommy in Cali

          from San Diego, CA

          About Me First Time Parent

          Pros

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

          Cons

            Best Uses

            • Infants
            • Toddlers

            Comments about Britax Marathon 70-G3 Convertible Car Seat - Onyx:

            I have researched car seats since before my first baby. Britax tests their seats at a faster rate of speed than other seats. Safety is worth paying a few extra dollars. My 6 week old hated her infant seat and so we upgraded to this seat sooner than we would have. We love it, and my baby loves it. Fantastic product.

            Comment on this review

            Displaying reviews 1-8

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