Will lightweight foam stairs hold a large dog?

It depends on the build. Verified-purchase reviewers report foam stairs from brands like Best Pet Supplies and EHEYCIGA handling 60–85 lb dogs, and a few report higher. However, high-trust r/dogs commenters repeatedly warn that lightweight foam or plastic units can slide when a big dog pushes off them, and several recommend a heavier wooden ramp or step for dogs over roughly 90 lbs.