I purchased these to add to our traditional climbing wall. They are plenty strong for dry tooling and have plenty of purchase to pull of the craziest of moves. To protect our existing wall, I bolted the hold on to a plywood backer board (6" x 12") with a "T" nut then bolted the board to our climbing wall. They work great and have a ton of options, if you rotate them for variety. I may buy a second set.