Xit Tripod Dolly - 2pk

I was going to give it five stars because it works with both my 48" Zeikos tripod and my 75" professional Vivitar 3-way tripod but two legs got jammed when I opened them to work.After I tried both tripods I was closing the legs and one of the legs locked. I couldn't maneuver it to close like the other two. Losing my temper-cuz I have a quick one-I pulled the leg closed only to have one of the knobs (two silver circles in the middle of the dolly) pop off. The little metal thing which I thought was a screw slid inside one of the legs and a spring popped out. I tried to get it back to the way it was but ended up losing the spring inside the leg as well.After vigorously shaking this dolly both metal-whatever that thing is-came out and the spring. I managed to fix that but had it happen again with another leg. I tried to gently close it but it wouldn't work so I had to yank that one closed scraping some paint off of the little locking hole.So needless to say I have to be careful how I open this dolly. That locking mechanism works so well it keeps me from being able to close it and put it in the bag.