The Britax One4Life Slim ClickTight All-in-One car seat has a mile-long list of features: a robust ClickTight belt-tensioning lockoff panel, a top harness slot height higher than most harness-to-booster seats, a top shoulder belt guide higher than most dedicated belt-positioning booster seats, flame retardant-free machine washable fabrics, and more! What else could we talk about in our review? Plenty.

If you’re at all familiar with Graco car seats, you know they love to have confusing, similar names. With three, yes 3, versions of the SlimFit, it’s super important to know which one is the skinny one if you’re looking to have a 3-across in your back seat. They’re all awesome seats, but one is skinny while the other two are not.

Slim and ultra-narrow car seats are a hot trend right now. And while this new trend has been a godsend for many parents and caregivers looking to squeeze 3-across in their vehicle, it’s quite possible that the looming side-impact standard (FMVSS 213a), which will take effect on June 30, 2025, will force the discontinuation of some narrow harnessed car seats that aren’t able to comply with the stringent new requirements.

The Graco SlimFit3 LX 3-in-1 carseat is the industry standard when it comes to narrow carseats. Need to get 3-across in your back seat? It’s likely you turn to the SlimFit3 LX first. What makes it so great? We dive deep in our review to show you all the pros and cons so you can make an informed decision before you buy.