The 16 screw-on footholds only feature in the 2017 and 2019 Setups and are optional. They allow an additional foothold rule when setting or searching for problems. In the filters section of the MoonBoard app, under the “foot rules” section, select “Screw-on only” to filter problems which use these footholds. Using the screw-on footholds can significantly reduce the grade of the MoonBoard problem. Note: The only difference between these footholds and the bolt on footholds is the colour and fixing type.