These pets stairs are very light weight and some what compact and say they can support up to 150lbs.  I have 140lb Newfoundland who took one look at them and said...NOPE !  I ain’t climbing those things !  While they say they can support up to 150lbs, I believe that is a slight  exaggeration.  They aren’t wide enough nor are the stair treads deep enough to accommodate an animal with such girth.