<mujoco model="square-nut">
  <asset>
    <texture file="../textures/metal.png" type="2d" name="tex-metal"/>
    <material name="metal" reflectance="0.7" texrepeat="10 10" texture="tex-metal" texuniform="true"/>
  </asset>
  <worldbody>
    <body>
      <body name="collision">
        <geom pos="-0.03325 0 0" size="0.0105 0.04375 0.01" type="box" solimp="0.998 0.998 0.001" solref="0.02 1" density="100" friction="0.95 0.3 0.2" rgba="0 0 1 1" group="1" condim="4"/>
        <geom pos="0.0 0.03325 0" size="0.03125 0.0105 0.01" type="box" solimp="0.998 0.998 0.001" solref="0.02 1" density="100" friction="0.95 0.3 0.1" rgba="0 0 1 1" group="1" condim="4"/>
        <geom pos="0.0 -0.03325 0" size="0.03125 0.0105 0.01" type="box" solimp="0.998 0.998 0.001" solref="0.02 1" density="100" friction="0.95 0.3 0.1" rgba="0 0 1 1" group="1" condim="4"/>
        <geom pos="0.03325 0 0" size="0.0105 0.04375 0.01" type="box" solimp="0.998 0.998 0.001" solref="0.02 1" density="100" friction="0.95 0.3 0.1" rgba="0 0 1 1" group="1" condim="4"/>
        <geom pos="0.054 0 0" size="0.02525 0.015875 0.01" type="box" solimp="0.998 0.998 0.001" solref="0.02 1" density="100" friction="0.95 0.3 0.1" rgba="0 0 1 1" group="1" condim="4"/>
      </body>
      <site rgba="0 0 0 0" size="0.005" pos="0 0 -0.05" name="bottom_site"/>
      <site rgba="0 0 0 0" size="0.005" pos="0 0 0.01" name="top_site"/>
      <site rgba="0 0 0 0" size="0.005" pos="0.11 0.06 0" name="horizontal_radius_site"/>
    </body>
  </worldbody>
</mujoco>