I just installed one to concrete (used concrete screws to hold in place) and there's plenty of room for two 3/4" garden hoses with room left over. They appear to be well constructed, but I have no history of of their performance over time.However, they do not work for my purposes because I have to travel over them with my powered wheelchair; it high-centers on the ramp (my chair has a clearance of 1 1/2 inches). The high point of the ramp is 1 3/4" so I can make a run at it, but that's not good for the chair or the ramp. I'll figure it out, but out-of-the-box you could have the same issue with accessibility. Discover your clearance issues before purchasing; I didn't ??