Here is a mandatory gear list of what I have for the Arrowhead 135. Definitely could be improved, but a good start. I'll try and get a recommended gear list up soon as well. That is the list of equipment that you use to make up the rest of the 15 lb minimum.
Mandatory Gear List (15 lbs at ALL times) -20 Sleeping Bag – The North Face Tundra Polarguard Delta Regular Length 3 lbs 15 oz Insulated Sleeping Pad – Therm-a-Rest Prolite 4 Regular 1 lb 8 oz Bivy Sack or Tent (NO space blankets) – Bibler Bipod Bivy 1 lb 13 oz Firestarter (Matches or Lighter) – Coghlan’s Windproof/Waterproof Matches 0.25 oz Stove to heat water – MSR Whisperlite International Stove 14 oz 8 fl oz of Fuel at all times – MSR 11 oz Fuel Bottle filled with White Gas 2.7 oz bottle / 11 oz white gas Pot (min volume 1 pint) – Snow Peak Titanium Folding Cup (Holds 21.2 oz) 2.8 oz 2-qt insulated water container – 2 Nalgene Lexan 1 qt Water Bottles 6.4 oz each empty - 2 Outdoor Research Water Bottle Parkas 5 oz each Headlamp or Flashlight – Cateye HL-EL410 Compact Opticube 2.6 oz including batteries Flashing red light (both front and back) – 2 Knog Frog red LED lights 0.7 oz each including batteries Whistle on string around neck – Coghlan’s Survivo II 5-in-1 1 oz 1-day of food at ALL times (3000 calories) – 1 lb of butter 1 lb Total Weight = 12.07 lbs