Hinge equivalent to RUmRUvRUmRUv

<br>

Equivalently:

<ul>
<li>Start from RmUmRvUmRvLmRvUv
<li>Lower 90 degrees the flap tile pointing up against the other flap tile
<li>Lift 90 degrees a pair of adjacent tiles (one is the former flap tile)
    into the final shape
</ul>