This pack gives you a bit more room than the 28 size. Also great for horizontal & vertical caves, and includes grommets on the sides and bottom which makes it great for wet caves as well.
 
Features:
Comfortable, padded and adjustable shoulder straps.
Upper, bottom and two handles on the back.
Integrated tether rope “Anti-Twist" system.
Upper loop for hauling.
Asymmetric drawstring closure.
Multiple eyelets on bottom and sides for better water drainage.
Reinforced seam on the bottom.
Options for a waist belt and compression webbing.
 
Specifications:
Volume: 33 litres
Dimensions: height 65сm, base diameter 25,5сm
Capacity: approx. 100m, 10,5mm super static rope
Nett weight - 1015g.
Materials: PVC 900g/sq.m., polyester webbing, acetal (POM) buckles