Getting ready to do the Knobstone trail in Southern Indiana. I’m going to use a setup that’s been working well for me lately.
At 22 oz the Mountain Hardware Splitter 20 (23L really) isn’t all that light, but I’ve had my fill of wimpy, small volume (18L to 23L) SUL packs. It seems like they have to be packed just right and be kept nearly full or else they’re not comfortable. Not so with the Splitter. It features a hard, thermoplastic urethane framesheet combined with exterior back padding that runs vertically on each side of the spine. It also has interior padding on the laptop/water bag pocket, This creates a pack can be loaded half full of canned goods (if someone so desired, God forbid) and still ride comfortably.
I place a cut section of blue REI foam in the pocket to help enhance the back padding even more. The pad serves double duty by placing it under the shoulder portion of a Klymit Inertia X Lite, where it needs it most. I love the clamshell design.
I carry most of my water on a belt and shoulder sling, but the MH Splitter has 2 side pockets that are plenty big enough for 1 liter Gatorade bottles. The robust 400d nylon insulates far better than mesh too. Pack also has a large side-zip front storage pocket (brighter yellow) that holds a lot.
I’m able to use a small pack like this on a 3.5 day thru (resupply half way) because I carry 2 liters of water and a storage pouch on a belt/shoulder sling combo. I just took 2″ wide nylon webbing and put holes in it with a hot nail and then tied on an Outdoor Products 1 liter bottle holder and an Eagle Creek pouch to the belt with spectra line. The bottle has to be in just the right position (cleft of gluteus) or it doesn’t ride right. I added a strong Nexus buckle on front. The entire belt (w/ bottle) weighs 8.2 oz. 
On the right side I carry a 1 liter shoulder sling bottle holder (3.8 oz w/bottle) that’s attached to the belt with a mitten hook to keep it from moving backwards or forwards. The belt and sling together allows me to free up lots of space in the pack and keeps about 5 pounds off of the pack as well.
I used Velcro and the axe loops to secure a folding sit pad that I also use to cushion my feet while sleeping.
Other packed items include:
1) ZPacks Solo Hexamid (.74) with Polycro and 8 Toaks titanium V stakes 20.7 oz.
2) Montbell UL SS 800 #5 in ZPacks roll top dry bag 18 oz
3) Klymit Inertia X-Lite 5.9 oz
4) Helium II Jacket XL 7.1 oz
5) Exped UL pillow w/ fleece cover 2.9 oz
6) Sawyer mini (average) 2 oz
7) EBY-265 400 ml ti cup w/ Esbit stand and windscreen 3 oz
8) 9 Esbit cubes 4.5 oz
9) Ion headlamp 1.9 oz
10) Golite beanie 1.4 oz
11) ccf pads 3.3 oz
12) Evernew 1.5L bag and other assorted smaller items 7.4 oz.
Total BPW (w/belt and sling) 7 lbs. Not SUL, but I like the way the weight is distributed better than with just a pack alone. The belt/shoulder sling keeps the pack weight down and the entire center of gravity lower. What’s more, the Splitter 20 is comfortable, no matter how it’s loaded.
