<mujoco model="square-nut">
  <worldbody>
    <body name="square_nut" pos="0.35 0.2 0." quat="0 0 0 1">
      <freejoint />
      <geom condim="4" density="100" friction="0.95 0.3 0.2" group="1" pos="-0.03325 0 0" rgba="0 0 1 1" size="0.0105 0.04375 0.01" solimp="0.998 0.998 0.001" solref="0.02 1" type="box" />
      <geom condim="4" density="100" friction="0.95 0.3 0.1" group="1" pos="0.0 0.03325 0" rgba="0 0 1 1" size="0.03125 0.0105 0.01" solimp="0.998 0.998 0.001" solref="0.02 1" type="box" />
      <geom condim="4" density="100" friction="0.95 0.3 0.1" group="1" pos="0.0 -0.03325 0" rgba="0 0 1 1" size="0.03125 0.0105 0.01" solimp="0.998 0.998 0.001" solref="0.02 1" type="box" />
      <geom condim="4" density="100" friction="0.95 0.3 0.1" group="1" pos="0.03325 0 0" rgba="0 0 1 1" size="0.0105 0.04375 0.01" solimp="0.998 0.998 0.001" solref="0.02 1" type="box" />
      <geom condim="4" density="100" friction="0.95 0.3 0.1" group="1" pos="0.054 0 0" rgba="0 0 1 1" size="0.02525 0.015875 0.01" solimp="0.998 0.998 0.001" solref="0.02 1" type="box" />
      <site name="square_nut:bottom_site" pos="0 0 -0.05" rgba="0 0 0 0" size="0.005" />
      <site name="square_nut:top_site" pos="0 0 0.01" rgba="0 0 0 0" size="0.005" />
      <site name="square_nut:horizontal_radius_site" pos="0.11 0.06 0" rgba="0 0 0 0" size="0.005" />
    </body>
  </worldbody>
</mujoco>