Stuff in zippered compartments on your back is asking to be robbed.
The Traffic Cone Bag, worn with the black pocket against your back and closed tight, is "lite" security by design - light fingers can't get at your stuff without slashing it with a knife.
I learned something about this from my advertising days at Saatchi:
Q: How do you carve an elephant from a block of wood?
A: Take a block of wood and remove everything that's not elephant.
Minimalist industrial design has always been my first love.
When designing this bag to be 'everything you need and nothing you don't', I found myself re-thinking the actual wearing process, and how that interaction with the body might influence the design.
For example, you need somewhere to put your cellphone. This would normally suggest a pocket with some kind of closure - a zip, button, that awful velcro stuff that rips into delicate fabric if you brush against it - to keep it secure.
In the above picture, Linda is wearing the bag with the large black pocket against her back rather than facing out.
Not only is the patch pocket deep enough to drop items into and have them stay there, wearing the bag in this way replaces the need for a zip.
What's wrong with a zip? Adds cost, bulk, and looks like, well, a zip. It's just not minimal, and the zip can catch and break.
I have though, conceded to adding a single snap closure you can eyeball on this post. That's to stop the lip from gaping somewhat when open.
Of course there's nothing wrong with these closures. But unless you're specifically designing a bling thing (and I like crazy bling too), re-thinking how an object is used in a holistic sense leads to no more - or less - than a perfect elephant.
TCB security at your favorite bar