Britax Marathon 70-G3 Convertible Car Seat

by Britax USA

• 100% Polyester
• 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
• 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

Product Description

Color: Onyx

Amazon.com

Packed with comfort and safety features, the BRITAX MARATHON 70-G3 Convertible Car Seat is designed with 360-degree protection to keep your child secure in the event of a crash. It offers high-density comfort foam for extra support, a cushiony cover, and an EZ-Buckle system for convenience when harnessing your child. The MARATHON 70-G3 accommodates children rear facing from 5 to 40 pounds and forward facing from 20 to 70 pounds.

MARATHON 70-G3
Convertible Car Seat
(Onyx)

At a Glance:

• Side Impact Protection system with energy-absorbing foam diverts crash forces
• Base with SafeCell Technology compresses to counteract forward momentum
• Energy-Absorbing Versa-Tether anchors seat and slows forward movement
• Integrated steel bars reinforce seat stability
• Tangle-free, no-rethread, five-point harness provides a secure fit

Age/Weight Requirements:

5 to 40 pounds rear facing; 20 to 70 pounds forward facing

Warranty:

Limited one-year warranty

With the Side Impact Protection system, energy-absorbing foam helps divert crash forces. View larger.

SafeCell Technology helps to minimize the risk of head injury during a collision. View larger.

The EZ-Buckle System maintains the harness buckle in a forward position to prevent your child from sitting on it when boarding. View larger.

Side Impact Protection System Diverts Crash Forces

The BRITAX Side Impact Protection system includes a rigid shell with deep sidewalls lined with energy-absorbing EPP foam to contain your child's head and body and divert crash force energy while creating a barrier against possible intruding objects. This system also protects your child's head and chest.

SafeCell Technology for Advanced Protection

The base of the MARATHON 70-G3 includes SafeCell Technology comprised of SafeCells, an engineered material designed to compress in a crash. This compression lowers the center of gravity to counteract forward rotation of the seat, helping to minimize the risk of head injury during a collision.

Located in the sides of the seat shell, integrated steel bars strengthen the connection to the vehicle and prevent forward flexing of the seat during a crash to reduce the risk of head injury.

In the event of a sudden stop, the Energy-Absorbing Versa-Tether strap restricts forward movement and reduces crash forces with patented staged-release webbing and a 2-point attachment. This webbing securely anchors the top of your child seat to your vehicle in either rear- or forward-facing positions.

No-Rethread Harness System and Comfort Features

The tangle-free, five-point harness allows for multiple height positions and can be adjusted without dismantling the harness or removing the car seat from the vehicle. Two buckle positions provide a snug, comfortable fit as your child grows. The seat's harness holders prevent the straps from getting in the way when you're putting your child in the seat, while the EZ-Buckle system maintains the harness buckle in a forward position to prevent your child from sitting on it when first entering the seat. Rear- and forward-facing recline options, as well as high-density foam cushioning, help your child relax on the journey. And the plush cover comes with matching comfort pads and an infant body pillow to keep children of all ages comfortable and secure.

Easy Installation and Airplane-Approved Design

The MARATHON 70-G3 takes the guesswork out of installing your car seat thanks to a range of convenience features. An anti-slip, contoured base grips and protects the vehicle seat. Premium lower LATCH connectors make for a quick, simple, and tight installation, while the push-button allows you to easily uninstall the car seat. And easy-to-access built-in lock-offs provide a secure installation when using the vehicle lap and shoulder belt.

The MARATHON 70-G3 has a durable cover that can be removed for easy cleaning without uninstalling the car seat. It's also approved for airplane travel.

Product and Warranty Information

The BRITAX MARATHON 70-G3 is made in the USA, has a seven-year life, and is backed by a manufacturer's limited one-year warranty.

What's in the Box

BRITAX MARATHON 70-G3 Convertible Car Seat, removable cover, comfort pads, infant body pillow, and user guide.

Click here to compare BRITAX car seats.

ROUNDABOUT 55

MARATHON 70-G3

BOULEVARD 70-G3

PAVILION 70-G3

ADVOCATE 70-G3

Trademark Information:

MARATHON™

SafeCell Technology®

Energy-Absorbing Versa-Tether®

Product Description

The Britax Marathon 70-G3 convertible car seat 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 fez-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 buckle and recline positions, comfort pads, and infant body pillow provide premium comfort and positioning.

Most Helpful Customer Reviews

250 of 260 people found the following review helpful

4.0 out of 5 stars Britax vs. Recaro (Britax Good but I prefer Recaro) August 14, 2012

By Justin Fevold

Color Name:Onyx

I have one each of the Britax Marathon and the Recaro ProRide for our two vehicles. I studied and agonized over the decision on which car seat(s) to get when I purchased them several months ago. There are a plethora of reviews that pit the Britax against the Recaro, so to save you reading time, I'll keep my review brief:

Pros of Both:
-Sturdy, High Quality
-Great padding
-Plenty of adjustment for a good secure fit (and our little girl is definitely behind the growth curve in weight: 1 year old and 17 pounds!)

Cons of Both:
-This is probably vehicle dependent, but if installing as rear facing then sometimes difficult to get it level because of how many vehicle seats slope down. Ultimately, in our Camry I followed manufacturer recommendations and used a tightly rolled towel underneath to achieve the right placement.

Reasons I like Recaro (I'll qualify this by saying both are good, this is just a preference and am probably splitting hairs):
-installation slightly easier due to nature of the latch belts.
-harness release is much easier to find and just seems to make more sense (ergonomically) based on how your hands work when you are reaching in the vehicle.
-seat seems less bulky and easier to transfer child in and out of.
-harness is easier to adjust and fit seems more snug (note on the Britax, fit is FINE, but we can't get any tighter so ideally it could be a hair better.
-shoulder pads stay in place better
-easier for child to see out of (keep those eyes busy!)

So, these reasons may not seem like a big deal...which is what I would have said when I was researching.... I will close with saying, both are good, and I did not bother to return the Britax, BUT, if I had to go back several months and do it all over again, I would just get two of the Recaro ProRide models.

Happy researching! Read more ›

156 of 166 people found the following review helpful

5.0 out of 5 stars Another great seat from Britax August 1, 2012

By Karen in Mommyland VINE™ VOICE

Color Name:Onyx|Amazon Vine™ Review (What's this?)

Since 2001 I've been hooked on Britax car seats. The quality and ease of use of their seats puts them above their competition. When I was presented with the opportunity to review the Britax Marathon 70-G3 I jumped at the chance to see how it differed from the Marathon 70.

We own a Britax Marathon 70 so I decided to put it next to the Marathon 70-G3 for a side by side comparison. For the most part the seats are practically identical with a few small differences. The harness adjustor strap's release mechanism is the same, and I still find it awkward when compared to the Marathon and Roundabout 55 classic seats. Instead of pressing down, you need to press up. After nearly 11 years of dealing with seats that have easier releases, I still find this to be awkward. Harness height adjustment on this seat is a snap compared to the seats where you need to rethread the harness. You simply have to squeeze and pull (or push) to adjust the height of the harness straps. The ease of use for this function is on par with the simple adjustment of the back on a Graco TurboBooster. Parents who travel frequently and find themselves lugging their child seat through airports will appreciate the added touch of an area to clip the versa tether strap to be used as a carry handle.

The difference between the Marathon 70 and 70-G3 lies in the versa tether and the harness buckle. The versa tether on the new Marathon 70-G3 is energy absorbing and works to reduce forward movement and rotation in a crash. The seat also has the EZ-Buckle System which keeps the harness buckle in a forward position and keeps your child from sitting on the buckle. I can tell you that this feature is quite nice.... I have been using a Roundabout 55 Classic with our nine month old and I can't tell you how often she ends up sitting on the buckle and freaking out while I try to pull it out from under her. The new design really works nicely to keep the buckle out of the way when loading the baby into the seat. The design reminds me of the harness buckle on our B-Agile stroller.

Installation of this seat was a snap. I installed it both rear and forward facing in my Toyota Sienna and it was easily and securely installed in both positions. Because the seat is so large, it is possible that this seat may not fit well in smaller cars when used in the rear facing position.

Overall, this is a great quality seat that will keep your little one safe, comfortable and secure for many years. In the nearly eleven years that I've been using Britax seats, I have found each of them to be worth the price. Read more ›

94 of 112 people found the following review helpful

4.0 out of 5 stars Super Safe Seat, Onyx is Hot as Blazes August 7, 2012

By Jonathan E Lane

Color Name:Onyx

We are so happy that we bought a Britax Marathon. It is easy to install, super safe, and our long-legged kids are comfortable in it. My son (now 4) used it happily until my daughter turned 1. However, as soon as we had to move it from the center of the rear row, to one of the sides... the silver fabric of the Onyx heats up so fast, it burns my fingers to touch it. So, we keep a towel over it when not parked in the garage. In retrospect, we should have ordered a velour/cotton fabric that doesn't heat up so much.

40 of 50 people found the following review helpful

5.0 out of 5 stars LOVE LOVE LOVE September 20, 2012

By JESS MAL

Color Name:Onyx

I purchased the britax marathon 70 for my daughter when she was 8 months old. I researched for months and decided based on the fact it was rear and forward facing it was best for us. My daughter loves her seat and we will be buying another when our second dd is the same age. Yesterday our worst fear happened when my 2011 Chrysler 200 was struck almost head on by another vehicle. Hubby was ok and Natalie had only 2 scratches on either side of her neck from the straps. No bruises or anything!!! In combination with the safety of my car (which is totaled) I think the britax saved my daughter from serious injury. The first thing I did while at the hospital was get on here to order her new seat! Thank you britax!!!

20 of 24 people found the following review helpful

5.0 out of 5 stars Peace of mind September 22, 2012

By Jessica L Gonzalez

Color Name:Chili Pepper|Amazon Verified Purchase

Researching car seats is HELL! but worth it, right? Britax wasn't on my list for awhile due to the cost but after months of researching different convertible seats, this one won out. My priorities were safety, extended rear-facing capabilities, and ability to fit in my small car (ford focus). We used the Chicco Keyfit 30 until my baby out grew it and I was afraid that this wouldn't fit but now I have more room than before. Even with the Marathon fully reclined, both the front seats can be completely pushed back without a problem (with the car seat in the center position). It took my baby a couple of weeks to get used to it but now that she has, she loves it. I have peace of mind using the Latch system which clicks into the bottom positions of the seat plus has a tether strap so that it clicks into the top Latch as well even when rear facing (normally you'd have to be forward facing for this). The frame is metal and the seat has a lot of cushion. I spent a lot of time feeling seats in the store and you'd be surprised how many of them feel hard. I plan on using this seat until my baby requires a booster. I'm so glad that I spent the extra cash for this seat. It's very sturdy and stylish.