Quoted from Kcpinballfan:
Not knocking them cause they are a good idea but my dolly was 40 bucks and I can move a machine by myself. Is there something I'm missing with these?
Yes, I believe there is. There are many ways to skin a cat. There are even more ways to move a pin. You can use an old school Wico dolly, a hand truck, pin skates, tri-dollys, sliders, Escaleras and all different types of Harbor Freight lift conversions, just to name a few. Each has it's own advantages and disadvantages.
The hardware I see pictured above, which I have never seen before, appear to have one very big advantage over all those others methods. Assuming they are already installed on the game and you have one or more cohorts nearby, you can move a game damb fast with those things! Just unplug and go!
I very much approve.