As weve mentioned, the main compartment has a rectangular frame at the opening that pops open to allow access to the bags interior
Bought my Tech Pac 3 years ago going on 4, and has been threw every single kind of environment (rendering, muddy, rainy, snow, ice hail, extreme heat, etc) and its still in one piece
Backpack ($99) Here Patagonia has put together a stellar, go-anywhere backpack
Symposium proceedings were produced as a special publication of the American Fisheries Society (Philipp and Ridgway 2002)
This can mean that its a good idea to try a helmet on if possible before you buy it, or purchase from an online site that offers a good return/exchange policy