Shower door bottom rail
A quick learner from Illinois says:
August 6, 2016
This is the bottom rail of sliding doors. 27 1/2 inches long
Paul from SWISCO responded:
August 9, 2016
I'm afraid we don't have this exact guide, but we do carry the 10-139. Could you use this as a replacement? The way this guide functions, you don't necessarily need one continuous piece.