<mujoco model="cube_outer">
    <default>
        <default class="cube">
            <geom type="box" size="0.02 0.02 0.02" rgba="0.96 0.26 0.33 1.0" density="1240" solref="0.004 1" contype="3"
                  group="1"/>
            <site type="sphere" size=".005" rgba="0 1 0 1" group="5"/>
        </default>
    </default>

    <worldbody>
    </worldbody>
</mujoco>
