Like any of these trolley systems, they are a challenge to install, particularly with one person. However, after installed they work just fine, and it does the job. Very simple device, seems well built, although I haven't had much time to use it.
Love these use to make my own but after finding these I can’t build them for as cheap as I can buy from vevor. Plus the quality is very good. I was thinking no way these be good for the price so I bought one then 6 more.
Absolutely love these trolleys built a shop bridge crane hoist with them have 6-8 of them haven’t let me down test build quality is amazing plus vevor shipping is crazy fast too
I purchased a chain hoist and a trolley and they work beautifully. I also picked up a couple of straps and use them to pick up the front end of my commercial 72 inch lawnmower in my garage. It allows you to get to use the blades to change them easily, this is a good deal and also at a decent price.
dzimmerle 
