These Safety Step Stools are Safe, Sturdy, and Durable. If you need a step stool to provide that extra lift for your RV, boat, or horse trailer, these folding stepping stools are specifically designed for RV use. Weighing only 7 lbs. (large size, small is 4.5 lbs.) and folding to a mere 3" thick, they are easily handled, in and out of storage.