I recently discovered this picture from propstore.com which shows the original strapping rig used by Anthony Daniels and other actors portraying the Protocol droids in “Star Wars” (ANH). This particular strapping system was only used in ANH, and later replaced by a more simplified system for ESB and ROTJ.
The strapping consists of some kind of a shoulder piece which is held in place with velcro/zip on the fround, it looks like it has some hooks on for keeping either the shoulders or the arms from not sliding off. Two other straps keeps the rubber section up.
The joints (elbow and backside of knees) are exposed, showing the silver/gold covering pieces which is characteristic for the ANH-Threepio. This can be clearly seen in most scenes in the movie. This silver/gold covering was supposed to hide the black unitard from being exposed on areas where some space around joints was required – for ESB and ROTJ this area was black and covered with electrical wire.
I can’t stop picturing myself this guy walking around the set between takes, going for a cup of tea or a toilet break. I wanna do that too :), totally awesome.