Cura/resources/extruders/Geeetech_Dual_Extruder_0.def.json

{
    "version": 2,
    "name": "E0",
    "inherits": "fdmextruder",
    "metadata":
    {
        "machine": "Geeetech_Base_Dual_Extruder",
        "position": "0"
    },
    "overrides":
    {
        "extruder_nr":
        {
            "default_value": 0,
            "maximum_value": "1"
        },
        "material_diameter": { "default_value": 1.75 }
    }
}