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Listen, as a mom who’s been through the car seat years, I get it. Those adorable head supports and cozy strap covers at the baby store are practically calling your name. After all, aftermarket car seat accessories sold in a baby store must be safe, right?
Wrong. So very wrong.
The Hard Truth About Aftermarket Car Seat Accessories
Here’s the deal: if it didn’t come in the box with your car seat, it hasn’t been crash-tested with your car seat. Period.
There is no way to know how a head strap, a seat protector or anything else that doesn’t come with the car seat will change how your car seat performs during a crash. Even what seems like a minor addition, like harness strap covers, may alter the way the car seat is designed to perform in a crash. Which means, these aftermarket products could result in serious injury or death.
“But it says it’s safety tested!”
Oh, I hear you. The packaging makes some pretty convincing claims. But here’s what they’re not telling you: individual testing of a product doesn’t mean squat if it hasn’t been tested with your specific car seat model in crash scenarios.
Car seats go through rigorous crash testing. We’re talking multiple crash scenarios, different speeds, various angles, various installation methods — all to ensure your little one stays safe in the worst-case scenario. These tests are done with the car seat exactly as it comes out of the box.
Now, throw in an aftermarket product, and all those careful calculations go right out the window. That extra padding? It could compress differently in a crash. Those strap covers? They might affect how the harness grips during impact. You just can’t predict the results.
Let’s Break Down Some Popular Products
Bulking up
Here I’m talking about harness strap covers, infant support inserts, head pillows or bunting (or sleeping) bags. These extras can cause issues in a couple of ways. One, they may add bulk between the baby and the harness straps. We don’t want to add bulk here for the same reason we don’t want to add bulk with winter coats. During a crash that bulk can compress then the harness straps are not properly positioned or tight enough to properly hold baby.
Two, these items can push the child out of a safe position in the seat or push the child’s head forward, which can interfere with the child’s airway.
Options:
- A lot of car seats come with inserts (along with instructions on when to remove them as your child grows). If your car seat does not come with inserts, using tightly rolled receiving blankets along the sides (not over the top) of your infant and clear of the harness, can be a safe method to give additional support when needed.
- If your car seat didn’t come with harness strap covers and your child is aggravated by the strap on their skin, you can pull up their shirt to go between their skin and harness strap. Some manufacturers will have approved strap covers available for purchase. Check with the manufacturer to see if these are available for your seat.
- instead of a bunting bag that has padding underneath the baby, just use blankets over baby or a car seat cover that wraps the top of the seat and doesn’t put anything between baby and the harness straps.
Seat Protectors
Seat protectors go between the car seat and vehicle seat to “protect” your vehicle seat. Sometimes these interfere with the install. They can make you think you have a tight install when you actually don’t. Then in a crash, you have a loose install.
Sure your car seat may leave indents in the vehicle seat. But those should come out over time. Messes can get under the edges of the seat protector anyway, so you could get in the practice of limiting food and drinks and taking off dirty shoes for the car.
Car Seat Head Straps
If you haven’t seen them here’s a link to see some examples. They seem like a great solution to the sleep slump. These bands are meant to keep your sleeping child’s head from flopping forward. As a mom who’s watched her baby’s head bob around like a dashboard hula dancer, I can understand the appeal.
But here’s what the car seat manufacturers and safety experts say: these straps can actually cause serious injury in a crash. The head is meant to move forward in a controlled way during an impact. These straps? They can interfere with that forward-head movement, instead making the neck bend the other way as the head is being restrained.
Parents have reported the straps slipping down over the mouth or even to the neck causing a potential strangulation issue.
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Mighty Tite
This one is actually discontinued but you can still find it on ebay. So just in case you come across it. Might Tite claims to help you get a tighter car seat installation. Sounds great, right? Except car seat manufacturers are crystal clear: if you need a special tool to achieve proper installation, something’s wrong. Your car seat should install securely without any extra gadgets. Period.
MIghty Tite has been known over stretch and damage the vehicle seat belt. damage vehicle seats and damage the car seat. Over all, not a good product. Thank goodness it was finally discontinued.
ComfiGO by ClypX
Technically this is sold as a child restraint, not an aftermarket car seat accessory.
I actually didn’t heard of this or seen it advertised until someone wrote us saying: “I was pretty shocked at how widespread this one was being recommended — by travel bloggers, best products lists, parenting sites. It throws around safety certification claims a bunch and has some safety labeling on it (you can’t see the wording clearly in their pictures). It fooled me for a while.”
I have searched a few times for more information about the ComfiGO by ClypX but have been unable to find much on other car seat blogs (that are run by certified child passenger safety technicians (CPST)). What I did find was an article in Safe Ride News about how National Highway Traffic Safety Administration (NHTSA) issued a cease-and-desist order in 2022 against ClypX, stating that their previous and similar product, Smart Kid Belt, did not meet the federal definition of a child restraint system under FMVSS 213.
Their ComfiGO seems to be similar but with a slim “seating surface”. It is marketed as a seat belt positioning device and their website says it is certified to FMVSS 213 standards as a booster. My understanding, from what I could find, is it does not adequately meet positioning requirements for federally approved booster seats. I’m going to go with a “no” vote for this product.
What Actually IS Allowed?
I know, I know — I’m raining on everyone’s parade here. But there are some accessories that are okay to use:
- Items made specifically by your car seat manufacturer for your specific model
- Thin blankets tucked around your child AFTER proper harness adjustment
- Small rolled washcloths (not in place of manufacturer-approved padding) to help with fit
- Weather-appropriate clothing that doesn’t interfere with harness tightness
The Warranty Reality Check
Using any non-approved aftermarket car seat accessory with your car seat may automatically void its warranty. Worse? If you’re in a crash and that accessory interferes with the car seat’s performance, your insurance might not cover it. Is that cute head support worth the risk? Check your car seat’s manual to see what it says.
For instance the Chicco Next Fit manual says, “DO NOT use any accessories, pads, or products not included with this Child Restraint, unless approved by Chicco USA. Doing so will void the warranty of this Child Restraint.“
Bottom Line
I know these products are tempting. The marketing is clever, and the promises are big. But as someone who’s spent countless hours researching car seat safety (and yes, made some mistakes along the way), I’m begging you: stick to what’s approved by your car seat manufacturer.
Remember this: car seats are already designed, tested, and approved to protect our precious cargo. Adding anything extra is like throwing a wrench into a finely tuned machine. Your baby’s safety is worth more than any trendy accessory.
Have questions about your specific car seat? Check your manual or reach out to a certified Child Passenger Safety Technician. They’re literally waiting to help you keep your little one safe – no extra purchases required.
By Amie Durocher, Creative Director at Safe Ride 4 Kids and certified CPS Tech since 2004
Copyright 2025 Safe Ride 4 Kids. All rights reserved. You may not publish, broadcast, rewrite or redistribute this material without permission. You are welcome to link to Safe Ride 4 Kids or share on social media.
We originally published this post in July 2013. We updated the article for accuracy and comprehensiveness.
