It’s plastic, although nicely firm unlike squishy unreinforced vinyl pillows. This pillow solves the problem completely. It is much softer than a sofa pillow and yet more supportive than a bed pillow.

Medic-air pillows are the gold standard for correct seated lumbar support and alignment. This provides the lumba support that is missing from the car's seat. I have bad posture and this has helped.

Keep a spare on hand in case of getting puncture from sharp objects. I keep several - in my kitchen chair, sometimes my reclinder, often one in my purse, as they collapse flat and blow up easily. I embarrass my kids at times in restaurants by blowing ...  Read More

It inflates and deflates easily. When deflated it is easy to transport. It can be deflated and folded small to easily carry on a plane.

One of the pillow has a leakage somewhere & i have to fill it up every hour. Even just filled with a little air, the air moves around behind me while the car moves and it's hard as a rock (being air and not foam) go with thermarest instead.