Originally Posted by hoopics

We've checked our car seats probably a dozen or so times at this point, always using the plastic bags at the checkin counter. We buckle all the buckles, pull the straps tight, and then wind the strap ends up and tuck them under the padding of the seat so that they don't hang out of the bag. Tear a small hole in the back of the bag (back side of the seat), and pull both straps through so that the agent can put your bag tag around the straps. I've never had an issue with the bag arriving in one piece at my destination, but at some airports they route them to the oversized luggage drop-off belt.

As for the notion above that they are presumptively going to be destroyed by the baggage handlers, I will simply state: citation needed. I have never been asked to sign a liability waiver for a car seat. If they were routinely being delivered broken, you can bet your bottom UA would be shifting that risk to travelers, like they do for golf clubs in soft-sided bags and other frequently broken checkables.