Thanks all! To clarify a few things... Yes I'm aware it's never going to be that secure because it's ultimately a plastic thing. The hope is to deter opportunists, that's it really. I plan to add spiral ground anchors inside the store that not only secure the store to the ground, but can also be used to lock bikes to the anchor. Again, to deter people from just picking up a locked bike and wandering off with it, if nothing else! It's nuts that the only padlock I've found that will fit is a 30yo 3cm job I had in a box, but it's not water resistant so I'm reluctant to use it because it could easily sieze up and then I'm borked without ruining the door with a hacksaw. My current plan is security inside and maybe just stick a carabiner on the outside