Product review (1 stars): Don't bother
It claims to twist easily and wind up the cord.  Two of us couldn't manage it and had to wind the cord by hand.  My blinds are so long that this didn't really help allieviate the cord issue.  I had to leave the cord long enough to be able to pull up and down on the blind, but then the cord wind up hung so low that it was able to be reached by my toddler.  Do NOT get these if you have any intention of ever pulling up your blinds, they merely keep the cord up and out of the way if you only intend to twist open your blinds.