Bolt-on holds
If you are building a DIY wall with plywood you need good quality 18mm sheets prepared with M10 Tee nuts. Tee nuts are captive nuts that are hammered into the back of the ply before it is mounted, and enables holds to be interchanged without access behind the panel. To place a tee nut, drill a clean 12mm hole in the ply and hammer in the tee nut making sure that it sits squarely. It is always preferable to insert an excess number of tee nuts, as this will enable you to reconfigure your hold pattern many times.

Screw-on holds
These can only be used on a flat plywood surface and should be fixed with the screws provided using with an electric screwdriver set to low torque.