Zpacks Sub-Nero Ultra 30L Backpack

The Zpacks Sub-Nero Ultra 30L is a frameless ultralight backpack made from Ultra 100X, a laminated UHMWPE fabric weighing 3.3 oz per square yard. In its standard-strap, beltless configuration it weighs 302 g for a total capacity of 30 liters — 17 l in the main roll-top compartment plus 13 l spread across two side pockets — working out to about 10 g per liter carried. Rated to a 9 kg max load, it relies on the pack's shape rather than a frame or padded hip belt, using only webbing at the waist. The interchangeable strap system and removable sit pad let hikers adjust fit and add minimal back support without extra weight, while a chest strap keeps the load stable on the move. There's no hydration sleeve, no integrated rain cover and no front pocket, so this pack targets thru-hikers and ultralight weekenders who have already dialed in a minimal kit and don't need built-in redundancy for wet-weather or hands-free hydration.