Use tweezers to grab the folded aluminum that is holding the chain.

Use pincers to grab the other side of the aluminum and pull on opposite directions to unfold the aluminum and release the chain.

Use the second picture as a reference to place the tweezers and pincers. Then pull-on opposite sides to open. View the last picture for results.

To reassemble your device, instead of pulling to opposite sides, fold the aluminum to its original form with the new chain inside.