Time Life Lobby chair identification  

Hi all,

I am a dealer in the UK and have picked up these 2 HM Time life Lobby chairs. They came from a auction in German. I need some information on them if any one can help?

We have one pictured on the right seems to have a chrome frame and 6 fixing on the arms. It seems to be missing the material at the bottom, is this suppose to be hopsack? Also what sort of year and make would this be?

The one of the left  has an Alu frame and has 3 fixings to the arms. This seems an older model. The underneath of this one seems to have adjustable height but can't seems to move it and doesn't seem genuine to me?. It has a screw to fix in place and there is upholstered material with staples rather than leather, should this be the case? Has this been restored in some way? (See 3rd picture)?