I designed this pack for use on the Tour Divide Bikepacking Race. I carried the original during the 2017 race. This pack is under one pound, 500 grams, and is built in any back length for a perfect fit.
Fabrics are Xpack VX42, VX07, and 200D Spectra ripstop in the body. The shoulder straps, back panel, and waist belt are 3 mm spacer mesh for breathability and fast drying. The waist belt is a combination of spacer mesh and a durable stretch woven fabric that allows the belt to stretch and move with your body. the shoulder staps a have a thin, 1/4" (6mm), closed cell foam layer in the middle to help support the weight of a full load of water and food. the main zipper is a #10 YKK water-resistant zipper. The front pocket is a #8 YKK water resistant zip.
It can be rolled up and stored on the top of a seat bag if you don't need the overflow space. I use it to carry extra water, food and a layer or two depending on the weather. this way I never really needed to get into my closed bags during days of rain and/or snow.
This isn't a hydration pack, however, it does now have a bladder sleeve. There is a hose port. I used it to carry water in my MSR water bag and refilled my bottles. I can sew a clip for the MSR DromLite water bags if desired.
there is a blinky light strap on the back.
Sizing: available in back lengths 13"-23". shorter packs will be slightly deeper front to back to add some volume.
Colors: the main body is black ripstop with white(spectra fiber). the top zippered panel can be a custom color: black, navy blue, red, grey, yellow VX21 fabric.
weight: 19" pack is 14 ounces.