even when sitting upright the zero gravity chairs sit you back somewhat instead of upright... way too easy to slide all the way back and take a nap! These are also easier to get in and out of then the zero-gravity as they have strong and stable arm rests to push off on.
What makes them comfortable is the built-in back support that is not visible in the picture...
Patented technology represents an evolution of the traditional camp chair by adding exclusive, frame-integrated, lumbar support - all while maintaining the ease of use, light weight and portability people expect and appreciate in portable chairs.
Padded, ergonomic back support design allows you to relax against the comfortable lumbar support while preventing the uncomfortable leg-pinch from the fabric in the front of the seat that is common in many other chairs.