No frames, light weight construction, heavy-duty material, no flapping, water-proof, and it's easy to use. Pack light and GL looks small or pack heavy and GL expands while remaining secure on the bike without drilling holes in your plastic. 
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Get the weight off your back: The Mojavi saddle bags are durable and streamline; you'll never notice they are on your bike while riding. These work great on single track. 
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