Next road trip I am getting some headphones like the new Kidz Gear IR68KG02. The headphones are and are designed to be used with in-car DVD and video systems. The headphones will work with other devices as well if you buy the wireless transmitter available as an option.
Kidz Gear promises that the headphones are compatible 100% with all in-car systems that use IR technology. The best news is that the headphones are only $34.99. That is going to be a lot cheaper than the dealer will charge you to order a new set of headphones if yours are lost or broken. The headphones are available now.