Let me see if I have the distance - I want to say 17", but I better look.
Yup, that's right - from knot to handle.
But, over and over again I am reading it described in such a way that would seem impossible just by looking at the photos. With that type of cord and the assumed twisting design of the device, it would seem that once the killer walked away, the tension on the neck would have been gone. Am I confused? Gosh. Just typing that made me queasy.