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Britax Marathon G4 Convertible Car Seat - Onyx

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Britax Marathon G4 Convertible Car Seat - Onyx - Britax  - Babies"R"Us
Britax Marathon G4 Convertible Car Seat - Onyx - Britax  - Babies"R"Us
Britax Marathon G4 Convertible Car Seat - Onyx - Britax  - Babies"R"Us
  • $289.99
  • $232.99
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Things to Know

  • This Item is included in our Car Seat Finder Comparison Tool
  • Gift wrap is not available for this item.

  • 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™ convertible car seat is designed for children rear facing from 5 to 40 pounds and forward facing from 20 up to 65 pounds. The MARATHON 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 MARATHON also incorporates BRITAX Side Impact Protection, offers a no-rethread and quick-adjust five-point harness, multiple buckle and recline adjustments, and an easy-remove cover that also allows access to belt paths from the front of the seat. A head and body pillow is provided for extra comfort and infant positioning.

The Britax Marathon G4 Convertible Car Seat Features:

  • Base with SafeCell Technology®
  • Energy Absorbing Versa-Tether®
  • Side Impact Protection
  • Harness Ultra Guard System (HUGS™


Britax has been a pioneer in child passenger safety for more than 35 years, with a legacy of leadership in developing innovations that enhance the safety of child car seats and improve their ease of installation and use. Their uncompromising focus has made Britax the best-selling child seat in Europe and one of the brands most trusted by American parents and caregivers since entering the U.S. market in 1996.
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® 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
  • Harness Ultra Guard System (HUGS™ provides resistance to forward movement in the event of a crash

Additional Info

286475

E406D5EE

652182711504

E9LQ91A

5 lbs

65 lbs

Convertible

Latch,Adjustable Head Support,5 Point Harness

Yes

4

22.4 pounds

29.8 x 19.4 x 18.8

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

Average Customer Rating:

by PowerReviews
Britax Marathon G4 Convertible Car Seat - Onyx
 
4.7

(based on 32 reviews)

Ratings Distribution

  • 5 Stars

     

    (23)

  • 4 Stars

     

    (8)

  • 3 Stars

     

    (1)

  • 2 Stars

     

    (0)

  • 1 Stars

     

    (0)

100%

of respondents would recommend this to a friend.

Most Helpful Positive Review

 

good solid seat

the only thing we don't love about it is that the velcro mean to hold the straps out of the way doesn't work well. Our other brand carseat has actual holders for the belts...Read complete review

the only thing we don't love about it is that the velcro mean to hold the straps out of the way doesn't work well. Our other brand carseat has actual holders for the belts that works better. This is not a big deal to me when compared to the safety features.

VS

Most Helpful Critical Review

 

hard to clean

Its easy to install and east to get child in and out of. The only thing i dislike about the seat is how hard it is to clean.the two year old i care for...Read complete review

Its easy to install and east to get child in and out of. The only thing i dislike about the seat is how hard it is to clean.the two year old i care for throw up in the seat and it took my forever to clean up. You can not take the car seat apart for cleaning.

Reviewed by 32 customers

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(0 of 1 customers found this review helpful)

 
4.0

Seems very sturdy

By OkMomma

from NorCal

Comments about Britax Marathon G4 Convertible Car Seat - Onyx:

I bought this as an additional carseat to our daily driver (a Safety1st Alpha Omega Elite). This carseat seems well built, however it does not have arm rests; the Safety1st does. However, I do like the steel bars. We've only had this a month so I don't know how it will hold up.

Comment on this review

(1 of 1 customers found this review helpful)

 
3.0

hard to clean

By Supernanny

from Pittsgrove, NJ, United States

Comments about Britax Marathon G4 Convertible Car Seat - Onyx:

Its easy to install and east to get child in and out of. The only thing i dislike about the seat is how hard it is to clean.the two year old i care for throw up in the seat and it took my forever to clean up. You can not take the car seat apart for cleaning.

Comment on this review

 
5.0

We recommend them to everyone!!!

By Mamajane

from Salt Lake City, UT, United States

Comments about Britax Marathon G4 Convertible Car Seat - Onyx:

We bought our first marathon for our son almost 7 years ago, have purchased 2 more since (had two more babies) and love them!!! They are very well made, not a single part is flimsy, they are very user friendly, and my kids all love them!! We recommend them to all of our friends, and they all love them too! I couldn't imagine owning another convertible seat! We loved the brand so much we recently purchased one of their infant seats for baby #4 coming soon!!!

Comment on this review

 
5.0

Feels Secure

By Trailrunner3

from Fairport, NY, United States

Comments about Britax Marathon G4 Convertible Car Seat - Onyx:

This is my fourth purchase of a convertible car seat, two Britax products, one GRACO and one Maxi Cosi. I think this is the best one. It has a substantial feel to it, doesn't budge in the seat, is comfortable for my daughter, was easy to put in, and is convenient for getting the little one in and out of the car. It was decidedly more expensive than the GRACO, but you get what you pay for. Peace of mind.

Comment on this review

(1 of 1 customers found this review helpful)

 
5.0

Easy to use/comfortable

By KCS44

from Tampa, FL, United States

Comments about Britax Marathon G4 Convertible Car Seat - Onyx:

Compared to other brands, Britax is easy to install/buckle. I feel like my child is safe in this seat.

Comment on this review

 
5.0

Safety and product performance!

By Janet

from Grand Forks, ND, United States

Comments about Britax Marathon G4 Convertible Car Seat - Onyx:

The Britax brand was recommended by friends as the most safe, durable and secure car seat system. They were SO RIGHT!

Comment on this review

 
5.0

Super Light!

By Jess

from Chicago, IL

About Me Parent of Multiples (Twins etc)

Verified Buyer

Pros

  • Easy to install
  • Lightweight
  • Safe
  • Sturdy
  • Stylish

Cons

    Best Uses

    • Infants
    • Toddlers

    Comments about Britax Marathon G4 Convertible Car Seat - Onyx:

    I haven't used this car seat yet but I can already tell I love it. I returned my Gracco one for this because it is rated #1 for highway safety! Not to mention there are no recalls on it!

    Comment on this review

    (0 of 1 customers found this review helpful)

     
    4.0

    Good & solid

    By Sara

    from NYC, NY, United States

    Comments about Britax Marathon G4 Convertible Car Seat - Onyx:

    Sturdy, comfortable. My daughter seems to enjoy sitting in this.

    Comment on this review

    (2 of 2 customers found this review helpful)

     
    4.0

    good solid seat

    By jgonzalez

    from NC, United States

    Comments about Britax Marathon G4 Convertible Car Seat - Onyx:

    the only thing we don't love about it is that the velcro mean to hold the straps out of the way doesn't work well. Our other brand carseat has actual holders for the belts that works better. This is not a big deal to me when compared to the safety features.

    Comment on this review

    (1 of 1 customers found this review helpful)

     
    5.0

    Easy, Comfy & Safe

    By MonkeysMommy

    from Bellevue, WA, United States

    Comments about Britax Marathon G4 Convertible Car Seat - Onyx:

    I have been looking for a new car seat for some time and all my searches kept pointing me back to Britax. My daughter's safety is my number #1 priority and I know Britax will not let me down.

    Comment on this review

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    Size Chart