An adjustable bent housing consisting of three tubular members arranged in end to end relation. Each of the tubular members has an interior bore. A first tubular member has a first axis. A second tubular member has a second axis. A central tubular member is centrally disposed between the first tubular...http://www.google.com.au/patents/US5343966?utm_source=gb-gplus-sharePatent US5343966 - Adjustable bent housing
