Cura/resources/extruders/flsun_sr_extruder_0.def.json

{
    "version": 2,
    "name": "Extruder 1",
    "inherits": "fdmextruder",
    "metadata": {
        "machine": "flsun_sr",
        "position": "0"
    },
    "overrides": {
        "extruder_nr": { 
            "default_value": 0 
        },
        "machine_nozzle_size": {
            "default_value": 0.4 
        },
        "material_diameter": { 
            "default_value": 1.75 
        }
    }
}