These are a clips for a roller blind that kept unrolling on its own due to gravity. I made these clips so it limits how far it unrolls. It can still be rolled up no problem  

These fit a blind that is roughly 38 to 45mm in diameter when its down to the maximum you want this to be rolled down.

Simply roll the blind down, so it is as far down as you want and put these clips over the blind. 

Hopefully this helps you as much as it did us.