How to pass material to SkinnedMeshRenderer?

Question

Unity

Good afternoon. Please tell me how to transfer the material to the SkinnedMeshRenderer, but not to key 0 but to key 1.

Screen

//Так он меняет первое значение
var view = character.GetComponentInChildren<SkinnedMeshRenderer>();
view.material = material;

//А вот так по идее должен бы поменять, но не меняет
var view = character.GetComponentInChildren<SkinnedMeshRenderer>();
view.materials[1] = material;

// Пробовал и так 
var view = character.GetComponentInChildren<SkinnedMeshRenderer>();
view.materials.SetValue(material , 1);

I just have the first material is the body, and the second material is the head, and the materials need to be changed from scripts, help me solve the issue.