It's a replacement for the IKEA PAX wardrobe Komplement Rail. It broke on a sunday so there was no other solution than to CAD it ;)
It's a pretty old model, which I designed a couple of years ago, but as you can see, it still works flawlessly.

Cheers

Here is a link to the rail:

KOMPLEMENT Kleiderstange, weiß, 100 cm - IKEA Deutschland