IMPORTANT: The channel thickness (thickness of bag flap) is only 0.18″ (4,6 mm) so this bag lock is suitable for somewhat thicker flap closures with some interfacing/stabilizers.
The flap must be have a compressed thickness of 0.18″ (4,6 mm) to fit in the top part.
The top part of the lock slides over the flap and is attached with the screws. You can always add some glue. You do not need to cut a hole in your flap or bag.
Attach the bottom side (with prongs) on the bag front using the provided washer, and using the same technique as you would for any magnetic snap.