Java:
The cage holds the tank from the top and bottom.
The sides cradle the sides.
The bungie wraps around and hooks to the pins with light pressure.
It cant rise up or drop down.
The bungie holds the tank tight against the back.
Look close you can see the 1/4" bolt that passes through the trailer and bolts the
frame to the tub, It is long enough to pass through the propane tank handle then I use a rubber washer and NYLOCK wing nut to tighten it all
down.
No movement and if the bungie would snap or get cut The tank is locked to the cage.