Objective Workshop messenger bags include a weatherproof roll top main compartment which can be used in either the “roll top” mode, or in the standard “flap down” setup. The cushioned shoulder strap consists of custom aluminum hardware that permits one-handed “on the fly” strap change. All shoulder straps are easily swappable for left or right shoulder setups. Made in U.S.A. with a life time service warranty.
More here: http://missionworkshop.com/products/bags/messenger/
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