The UL40 is a 35 - 50 lt capacity framless backpack made of Ultra 200 and Ultra100 (when available).
 
Some of its features would be:
 
Water Resistant
Frameless
Removable Padded Hipbelt
NOT seam sealed
 
 
The latest version of the UL40 is now only available in Ultra200 Black and Ultra100 Wolf Grey. 
 
WEIGHT: 13.4 oz (without hip-belt)
                    14.8 oz (with hip-belt)
VOLUME: 30 - 45 L
WEIGHT CAPACITY: 27 lb maximum
IDEAL WEIGHT CARRY: 19 lb
 
Torso: 17 inches
Height: 20 - 27.5 inches
Wide: 10.5 inches