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The liner provides the support structure for the bag this keeps the bag from falling over on itself. Other materials include ballistic nylon, vinyl waterproof tarp lining used to make the bag waterproof.
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Contemporary bags use thicker gauges of canvas and tarp shielding for the inner waterproof lining. Materials used in messenger bags are often more durable and water-resistant than other over-the-shoulder bags. Messenger bags provide more weather resistance than leather satchel-style school bags.
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Compared to a backpack, it is easier to place and remove text-books, notebooks and supplies from a messenger bag because they can be easily shifted to the side of the body, providing better accessibility. Many companies design messenger bags specifically for the collegiate market. Many college and high-school students and bicycle commuters use them for fashionable and functional purposes. Messenger bags have become fashionable in urban environments, among cyclists and commuters. Messenger bags are often used as a fashion accessory. Without a stabilising strap, the bag tends to swing around to the rider's front, making pedalling difficult. The top-opening one-strap design allows messenger bags to be easily swung around front so that their contents can be accessed without removing the bag.Ī true messenger bag includes a second, thinner, stabilising strap that is fastened either around the rider's waist or diagonally across the chest. Such features may include fittings for easy adjustment of the shoulder strap, quick release buckles, an adjustable hinged buckle, and the ability to attach accessories, such as lights, phone holsters, or U-locks. They typically incorporate features that make them suitable for cycling. Similar in function to backpacks, messenger bags ensure comfort for people carrying heavy and/or bulky items, while allowing easy access to the contents. Pre-dating today's messenger bags described herein as specifically for bicycle messengers, fashion brands had been creating "messenger style" bags modelled after military map case bags and document pouches featuring a shoulder strap intended for wear across the chest for over a century. Some Royal Mail carriers in the United Kingdom currently use large messenger bags to deliver mail in lieu of a postbag.
This design of bag has been used in the transportation of mail and goods by numerous types of messengers, including Pony Express riders, postal workers, messengers on foot (especially in ancient times), and bicycle couriers.
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