diff --git a/Assets/VRM10/Runtime/Components/SpringBone/VRM10SpringBoneJoint.cs b/Assets/VRM10/Runtime/Components/SpringBone/VRM10SpringBoneJoint.cs
index ec0abade2..3af0b98cf 100644
--- a/Assets/VRM10/Runtime/Components/SpringBone/VRM10SpringBoneJoint.cs
+++ b/Assets/VRM10/Runtime/Components/SpringBone/VRM10SpringBoneJoint.cs
@@ -8,6 +8,7 @@ using UnityEditor;
 namespace UniVRM10
 {
     [Serializable]
+    [DisallowMultipleComponent]
     public class VRM10SpringBoneJoint : MonoBehaviour
     {
         [SerializeField, Range(0, 4), Header("Settings")]
@@ -22,10 +23,88 @@ namespace UniVRM10
         [SerializeField, Range(0, 1)]
         public float m_dragForce = 0.4f;
 
-        [SerializeField]
-        public bool m_exclude;
-
         [SerializeField, Range(0, 0.5f), Header("Collision")]
         public float m_jointRadius = 0.02f;
+
+        void AddJointRecursive(Transform t, VRM10SpringBoneJoint src)
+        {
+            var joint = t.gameObject.GetComponent<VRM10SpringBoneJoint>();
+            if (joint == null)
+            {
+                joint = t.gameObject.AddComponent<VRM10SpringBoneJoint>();
+                Debug.Log($"{joint} added");
+            }
+
+            // copy settings
+            joint.m_stiffnessForce = src.m_stiffnessForce;
+            joint.m_gravityPower = src.m_gravityPower;
+            joint.m_gravityDir = src.m_gravityDir;
+            joint.m_dragForce = src.m_dragForce;
+            joint.m_jointRadius = src.m_jointRadius;
+
+            if (t.childCount > 0)
+            {
+                // only first child
+                AddJointRecursive(t.GetChild(0), src);
+            }
+        }
+
+        void GetJoints(Transform t, List<VRM10SpringBoneJoint> joints)
+        {
+            var joint = t.GetComponent<VRM10SpringBoneJoint>();
+            if (joint != null)
+            {
+                joints.Add(joint);
+            }
+
+            if (t.childCount > 0)
+            {
+                GetJoints(t.GetChild(0), joints);
+            }
+        }
+
+        [ContextMenu("Add joints")]
+        private void AddJointsToChild0()
+        {
+            var root = GetComponentInParent<Vrm10Instance>();
+            if (root == null)
+            {
+                Debug.LogWarning("not Vrm10Instance");
+                return;
+            }
+
+            if (transform.childCount == 0)
+            {
+                Debug.LogWarning("no children");
+                return;
+            }
+
+            AddJointRecursive(transform.GetChild(0), this);
+
+            // updater root
+            foreach (var spring in root.SpringBone.Springs)
+            {
+                for (int i = 0; i < spring.Joints.Count; ++i)
+                {
+                    if (spring.Joints[i] == this)
+                    {
+                        // found
+                        while (spring.Joints.Count - 1 > i)
+                        {
+                            // remove after this joint
+                            spring.Joints.RemoveAt(spring.Joints.Count - 1);
+                        }
+                        // get descendants joints
+                        var joints = new List<VRM10SpringBoneJoint>();
+                        GetJoints(transform.GetChild(0), joints);
+                        // add jonits to after this
+                        spring.Joints.AddRange(joints);
+                        return;
+                    }
+                }
+            }
+
+            Debug.LogWarning($"{this} is found in {root}");
+        }
     }
 }