They would be in many sets but they wouldn't have sold much seperately. They were called in TrackMaster Quarter Straight Rails and in Motor Road and Rail Adaptor Rails.
TrackMaster: http://discounttoyco.com.au/media/catalo...file_6.png
Motor Road and Rail: http://img1.wikia.nocookie.net/__cb20130...ilsbox.JPG
TrackMaster: http://discounttoyco.com.au/media/catalo...file_6.png
Motor Road and Rail: http://img1.wikia.nocookie.net/__cb20130...ilsbox.JPG
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