Collapsible Carb Shaft Training Whip

I'm very short and I thought this whip would give me some flexibility and options to make me more comfortable training. I'll start with the positive, I really think the handle/grip is of good quality, aesthetically it's nice. But as far as function...I thought there would be a way to "lock in" at the desired length but instead the retractable part just go in and out as it moves around. It will not stay all the way in, all the way out, or in the middle. I have not used it with my horse yet but I will probably have to tape it into the length that I want which defeats the purpose of getting it.