How to set the visual and collision at ones using sdf to use the same geometry and pose

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Hi

I like to define the visual and collision apparans of a link at ones.
Is there a way to define variables?
Or is there a way to say visual == collision?
The example shows a link which has the same collision and visual dimensions is it possible to write that shorter:

<link name='Wall_01'>
  <pose>0 0 0 0 0 0</pose>
  <collision name='collision_01'>
    <pose>0 0.05 1 0 -0 0</pose>
    <geometry>
      <box>
        <size>5 0.1 2</size>
      </box>
    </geometry>
  </collision>
  <visual name='visual_01'>
    <pose>0 0.05 1 0 -0 0</pose>
    <geometry>
      <box>
        <size>5 0.1 2</size>
      </box>
    </geometry>
    <material>
      <script>
        <uri>file://media/materials/scripts/gazebo.material</uri>
        <name>Gazebo/Grey</name>
      </script>
    </material>
  </visual>
</link>

Thanks