We are a children's summer day camp. Years ago we took off all our bolt on holds and replaced them with screw on holds. We could not be happier. We use those holds on a 25ft outdoor wooden rock climbing wall . These Simple Jugs have the perfect shape and texture. They are large and easy to grab and look great. With screw on holds we never have to worry about spinners, they are quick and easy to put up, and we never have to worry about t-nuts rusting out. I would highly recommend these. We leave them outdoors, year round and they still look, feel and work great after 5 years.