Large Black

Get a Ridesafer vest, they’re great. Not as safe as a car seat (obviously) but for me the convenience is worth it.

No, don't need for any public transport. Even taxis don't require car seats, but might still be wise for safety. For rental cars, it's very cheap to add car seat option. If you travel a lot with a kid, I recommend getting [https://www.amazon.com/RideSafer-Lightweight-Convenient-Everyday-Rideshare/dp/B07WMTQHCL/](https://www.amazon.com/RideSafer-Lightweight-Convenient-Everyday-Rideshare/dp/B07WMTQHCL/), it's very compact and saves a lot of headache.

either order a car with a seat (in NYC) or now use a ridesafer vest since he’s big enough.

I also have one and it helped a lot when traveling. I bought it on FB marketplace.

Also like the ride safer vest. FWIW, bubble bum did not work well for us and, imo, did not position my kids or the belt as safely. (It was okay for my 9 year old, but not great for my 7 year old. Both my kids are small for their age.)