We get tires from Costco and nitrogen is what they use. I'm not a stickler for the nitrogen if I need air however.Couldn't see any obvious dry rot.
You have a green valve stem caps, which usually means you have Nitrogen gas in the tire - please don't bother putting any in your next set as it really is a waste of time, money, effort.
Many people believe some of the stories - just Google and you'll find many non-technical sites that expound the loose benefits - while most technical sites and tire manufacturers (such as Goodrich for one) don't prefer air or Nitrogen.
Here's a good read from AAA to help save you money and steer clear of the latest hype...
--->> Click It! <<---
Thanks