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Britax Marathon 70-G3 Convertible Car Seat

Britax Marathon 70-G3 Convertible Car Seat


4.8 out of 5 stars
  • 5 Stars93%
  • 4 Stars5%
  • 3 Stars1%
  • 2 Stars1%
  • 1 Star0%
4.90 / 5 based on 148 Reviews

Product Description

Minimize Forward Movement in Crashes The Britax Marathon 70-G3 convertible car seat accommodates children rear facing from 5 to 40 pounds and forward facing from 20 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. see more...

Top Questions See all 21 Q&A

Britax Marathon 70-G3 Convertible Car Seat
Britax Marathon 70-G3 Convertible Car Seat
Reviews (148)
Q&A (21)
Leave a Review
  • "I wish I knew a little more about car seats when I bought it as I didn't realize that it wasn't meant for taller children as they outgrow it rear facing quickly." in 13 reviews
  • "love this car seat especially the print and that it is very safe has lots of padding and is very comfortable " in 9 reviews
  • "It's easy to install, is heavy duty, and makes me feel comfortable putting my son in it because of the high safety ratings! " in 5 reviews
  • "My 3 year old is still rear facing comfortably in this seat :) It's comfortable, easy to install and has so many added safety features." in 4 reviews
Amanda G.
murray, KY
162 reviews
best car seat ever. they ha E wonderful safety rating and get good rating with Co sumer reports. they are very cushioned and soft for baby. I love that they come withe the soft belly pad and soft strap covers. you can get the cutest covers as well. you won't be disappointed. I loved knowing how safe my bundle of joy was in her britax
Jennifer T.
Wewahitchka, FL
93 reviews
I am a BRITAX MAMA!!!!! I'm very loyal to this brand for several reasons and I have had almost every type of car seat they make (marathon, roundabout, infant carrier, etc). They are well made, study, safe, and comfortable for my child. The infant seat was a little heavy, but that made me feel like she was safe
D H.
Rochester, NY
33 reviews
Love how comfortable my boys feel sitting in them. Expensive compared to other brands but it gives peace of mind and comfort. Great for traveling. We are constantly transporting the kids to this is great value. Really, cut corners elsewhere but when it comes to the kids safety, these are valuable spending.
Carolyn G.
Annapolis, MD
51 reviews
This is the second Britax marathon we have bought. We got this one when my 2nd child hated the recline of the infant bucket seat. He was able to remain rear-facing in this seat past his 2nd birthday.
I appreciate the longer lifespan of Britax seats, our 3rd child is still in this seat rear-facing at 2.5.
Rachel V.
31 reviews
My daughter has used this car seat since the day she was brought home, and we still love it. It's so easy to adjust when she grows, and much easier to move from car to car than our other convertible car seats. They're light, simple to "assemble", and gets great safety ratings from all the reputable reviewing websites.
Raegan Q.
16 reviews
purchased after my son & I were in a car accident. I love this seat. Pattern is cute. Easy to install. My son will be 3 in March and is still rear facing. Safety first! I did a ton of research before purchasing and would by again in a heartbeat!
Samantha  R.
448 reviews
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Mega Parent Expert
Level 3
Very cute car seat! Love the pattern and so does my boy. A bit pricey but it's a very good car seat and is very safe. Definitely recommend to any one who is in search of a car seat that they want to keep their babies safe in
Danielle K.
Michigan City , IN
106 reviews
I received one as a gift and it has been a blessing. I did some comparing to others and am very pleased with this one. My daughter is totally comfortable facing backwards in this chair. It is somewhat bulky so we leave it in our car but it's not a big deal to get it out and get it back in. Would definitely recommend!!
alysse h.
San Antonio, TX
45 reviews
Absolutely love this carseat. My daughter fits so comfortably and seems to enjoy being out of the infant carseat. I love that it is top rated in safety, which was the most important factor in our purchase. Price was was fair and I would definitely recommend to any other parent.
Rochelle C.
Salem, OR
28 reviews
I absolutely LOVE this car seat for so many reasons. It fits many ages/stages it's easy to put in and move from car to car it's not extremely complex to take apart for cleaning. It's worth every penny and I would purchase this seat again and again if necessary for any children to come.
Martha A.
Ramona , CA
130 reviews
At what age did you forward face your little ones?
Kathie M.
Maricopa, AZ
56 reviews
Will this totally ruin your leather? We are looking for a good car seat but worries about ruining our leather in our car.
Laura W.
Vancouver, WA
27 reviews
How heavy is this seat and is it easy to hook in?
Jelena K.
Jersey Vlg, TX
110 reviews
Can you use this rear facing for a newborn?
Tessla D.
Indio, CA
79 reviews
I loves these car seat if I can only afford one. LOL What age would you say you put your kid in one?

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