{
  "metadata": {
    "id": "servo-horn-25t-futaba-6mm",
    "name": "Servo Horn Set — 25T Futaba 6mm",
    "type": "mechanical_accessory",
    "schema_version": "1.4.0",
    "version": "0.2.0",
    "description": "Assorted servo heads (round, cross, T, etc.) with internal 25-tooth, ~6 mm Futaba-style spline bore for mounting to standard RC servo output shafts.",
    "manufacturer": "Generic",
    "datasheet_url": "https://futabausa.com/product/s-u301-standard-servo/",
    "tags": [
      "servo",
      "horn",
      "head",
      "spline",
      "25t",
      "futaba",
      "6mm",
      "round",
      "cross",
      "arm"
    ],
    "taxonomy": [
      "mechanical.adapter",
      "actuator.motor.servo"
    ]
  },
  "domains": [
    {
      "domain": "mechanical",
      "resources": [
        {
          "id": "spline_bore_25t_6mm",
          "name": "25T Spline Bore",
          "description": "Internal involute spline compatible with Futaba-style 25T servo shafts; nominal major diameter ~6.0 mm.",
          "functions": [
            {
              "name": "mechanical_mount",
              "description": "Torque-transfer mounting to a servo output spline",
              "direction": "bidirectional",
              "shareable_with": [],
              "signal_class": "mechanical_drive"
            }
          ],
          "connector_type": "custom"
        }
      ],
      "interfaces": [
        {
          "id": "servo_spline_25t_6mm",
          "name": "Servo Spline 25T 6mm",
          "protocol": {
            "type": "mechanical_connection",
            "role": "mounting_point"
          },
          "requires": [
            {
              "function": "mechanical_mount",
              "count": 1
            }
          ],
          "max_instances": 1,
          "description": "Mates with servo output shafts having 25 teeth and ~6.0 mm major diameter (Futaba-style)."
        }
      ],
      "package_type": "custom",
      "metadata": {
        "mounting_method": "spline_bore_with_central_screw",
        "requires_special_tools": false,
        "mechanical_life_cycles": 1000
      }
    }
  ],
  "usage_notes": "Verify spline type before use. 25T Futaba (~6.0 mm) is common on standard servos; Hitec standard is 24T (C1), and some micro servos such as SG90 use 21T micro splines which are not compatible.",
  "application_examples": [
    "Linkage arms for steering or control surfaces",
    "Round hub for rotary attachments",
    "Cross/T arms for push-pull linkages"
  ],
  "compatibility_notes": "Compatible with servo outputs labeled 25T/6 mm Futaba-style. Not compatible with 24T Hitec C1 or 23T JR/Airtronics. Many micro servos (e.g., SG90) use 21T micro splines."
}