Yes, if you buy an angled bracket. I purchased a duel bracket since I didn't know if I wanted the legs straight or angled.
1.50 inch tapering to 7/8 inches
Steel of course.
Its a pine wood, hard and sturdy enough hold just about anything.
No they come standard with the screws in the package, but if you wanted you could change the screws, but why?
Yes I even used these on our otterman, so yes they can be used on a sofa.
It depends on how many you are putting on long couches and Ben's would need six to be safe also the longer the weaker
Of you use the short ones
No the foot is connected to and it has swivel to it in case floor is not level