The Festool bluetooth remote module is not compatible with the CTL SYS. Someone already created a solution to make the bluetooth kit compatible: (https://github.com/jenskueper/festool-ctl-sys-bluetooth).
Inspired by this solution I created a variant using a simple 433MHz based potential-free relay
Bill of materials:
Assembly instructions (photos in corresponding order):
Onshape document link: https://cad.onshape.com/documents/8d022367b2ef92ea7bd8c390/w/da0141e1fdc86b23b705758d/e/ae3bb626cc08202e9a9e8995?renderMode=0&uiState=63d6d80a5336de296232e3d
The author marked this model as their own original creation. Imported from Thingiverse.