These make for pretty useful bags…they attach right to the frame of the bike right underneath you for easy access while you are riding…these things attach and detach pretty easily …kinda limited with what you can put in them though.
Messenger bags today are something of an urban fashion icon, most notably related to stereotypical bike messengers on the streets of New York or L.A. The bike messenger bag is worn over one shoulder with a strap that winds around the chest resting the bag on the lower back.
These bags hook on right underneath your seat…these are pretty small too, but out of the way and good for holding little tools and extra goodies. An excellent spot for emergency supplies.